1/*
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>
5 *
6 * Fixed point code
7 * Copyright (c) 2013
8 *      MIPS Technologies, Inc., California.
9 *
10 * This file is part of FFmpeg.
11 *
12 * FFmpeg is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU Lesser General Public
14 * License as published by the Free Software Foundation; either
15 * version 2.1 of the License, or (at your option) any later version.
16 *
17 * FFmpeg is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20 * Lesser General Public License for more details.
21 *
22 * You should have received a copy of the GNU Lesser General Public
23 * License along with FFmpeg; if not, write to the Free Software
24 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 */
26
27/**
28 * @file
29 * AAC Spectral Band Replication decoding functions
30 * @author Robert Swain ( rob opendot cl )
31 * @author Stanislav Ocovaj ( stanislav.ocovaj@imgtec.com )
32 * @author Zoran Basaric ( zoran.basaric@imgtec.com )
33 */
34
35#include "libavutil/qsort.h"
36
37static av_cold void aacsbr_tableinit(void)
38{
39    int n;
40
41    for (n = 0; n < 320; n++)
42        sbr_qmf_window_ds[n] = sbr_qmf_window_us[2*n];
43}
44
45av_cold void AAC_RENAME(ff_aac_sbr_init)(void)
46{
47    static const struct {
48        const void *sbr_codes, *sbr_bits;
49        const unsigned int table_size, elem_size;
50    } sbr_tmp[] = {
51        SBR_VLC_ROW(t_huffman_env_1_5dB),
52        SBR_VLC_ROW(f_huffman_env_1_5dB),
53        SBR_VLC_ROW(t_huffman_env_bal_1_5dB),
54        SBR_VLC_ROW(f_huffman_env_bal_1_5dB),
55        SBR_VLC_ROW(t_huffman_env_3_0dB),
56        SBR_VLC_ROW(f_huffman_env_3_0dB),
57        SBR_VLC_ROW(t_huffman_env_bal_3_0dB),
58        SBR_VLC_ROW(f_huffman_env_bal_3_0dB),
59        SBR_VLC_ROW(t_huffman_noise_3_0dB),
60        SBR_VLC_ROW(t_huffman_noise_bal_3_0dB),
61    };
62
63    // SBR VLC table initialization
64    SBR_INIT_VLC_STATIC(0, 1098);
65    SBR_INIT_VLC_STATIC(1, 1092);
66    SBR_INIT_VLC_STATIC(2, 768);
67    SBR_INIT_VLC_STATIC(3, 1026);
68    SBR_INIT_VLC_STATIC(4, 1058);
69    SBR_INIT_VLC_STATIC(5, 1052);
70    SBR_INIT_VLC_STATIC(6, 544);
71    SBR_INIT_VLC_STATIC(7, 544);
72    SBR_INIT_VLC_STATIC(8, 592);
73    SBR_INIT_VLC_STATIC(9, 512);
74
75    aacsbr_tableinit();
76
77    AAC_RENAME(ff_ps_init)();
78}
79
80/** Places SBR in pure upsampling mode. */
81static void sbr_turnoff(SpectralBandReplication *sbr) {
82    sbr->start = 0;
83    sbr->ready_for_dequant = 0;
84    // Init defults used in pure upsampling mode
85    sbr->kx[1] = 32; //Typo in spec, kx' inits to 32
86    sbr->m[1] = 0;
87    // Reset values for first SBR header
88    sbr->data[0].e_a[1] = sbr->data[1].e_a[1] = -1;
89    memset(&sbr->spectrum_params, -1, sizeof(SpectrumParameters));
90}
91
92av_cold void AAC_RENAME(ff_aac_sbr_ctx_init)(AACContext *ac, SpectralBandReplication *sbr, int id_aac)
93{
94    if(sbr->mdct.mdct_bits)
95        return;
96    sbr->kx[0] = sbr->kx[1];
97    sbr->id_aac = id_aac;
98    sbr_turnoff(sbr);
99    sbr->data[0].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
100    sbr->data[1].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
101    /* SBR requires samples to be scaled to +/-32768.0 to work correctly.
102     * mdct scale factors are adjusted to scale up from +/-1.0 at analysis
103     * and scale back down at synthesis. */
104    AAC_RENAME_32(ff_mdct_init)(&sbr->mdct,     7, 1, 1.0 / (64 * 32768.0));
105    AAC_RENAME_32(ff_mdct_init)(&sbr->mdct_ana, 7, 1, -2.0 * 32768.0);
106    AAC_RENAME(ff_ps_ctx_init)(&sbr->ps);
107    AAC_RENAME(ff_sbrdsp_init)(&sbr->dsp);
108    aacsbr_func_ptr_init(&sbr->c);
109}
110
111av_cold void AAC_RENAME(ff_aac_sbr_ctx_close)(SpectralBandReplication *sbr)
112{
113    AAC_RENAME_32(ff_mdct_end)(&sbr->mdct);
114    AAC_RENAME_32(ff_mdct_end)(&sbr->mdct_ana);
115}
116
117static int qsort_comparison_function_int16(const void *a, const void *b)
118{
119    return *(const int16_t *)a - *(const int16_t *)b;
120}
121
122static inline int in_table_int16(const int16_t *table, int last_el, int16_t needle)
123{
124    int i;
125    for (i = 0; i <= last_el; i++)
126        if (table[i] == needle)
127            return 1;
128    return 0;
129}
130
131/// Limiter Frequency Band Table (14496-3 sp04 p198)
132static void sbr_make_f_tablelim(SpectralBandReplication *sbr)
133{
134    int k;
135    if (sbr->bs_limiter_bands > 0) {
136        static const INTFLOAT bands_warped[3] = { Q23(1.32715174233856803909f),   //2^(0.49/1.2)
137                                               Q23(1.18509277094158210129f),   //2^(0.49/2)
138                                               Q23(1.11987160404675912501f) }; //2^(0.49/3)
139        const INTFLOAT lim_bands_per_octave_warped = bands_warped[sbr->bs_limiter_bands - 1];
140        int16_t patch_borders[7];
141        uint16_t *in = sbr->f_tablelim + 1, *out = sbr->f_tablelim;
142
143        patch_borders[0] = sbr->kx[1];
144        for (k = 1; k <= sbr->num_patches; k++)
145            patch_borders[k] = patch_borders[k-1] + sbr->patch_num_subbands[k-1];
146
147        memcpy(sbr->f_tablelim, sbr->f_tablelow,
148               (sbr->n[0] + 1) * sizeof(sbr->f_tablelow[0]));
149        if (sbr->num_patches > 1)
150            memcpy(sbr->f_tablelim + sbr->n[0] + 1, patch_borders + 1,
151                   (sbr->num_patches - 1) * sizeof(patch_borders[0]));
152
153        AV_QSORT(sbr->f_tablelim, sbr->num_patches + sbr->n[0],
154              uint16_t,
155              qsort_comparison_function_int16);
156
157        sbr->n_lim = sbr->n[0] + sbr->num_patches - 1;
158        while (out < sbr->f_tablelim + sbr->n_lim) {
159#if USE_FIXED
160            if ((*in << 23) >= *out * lim_bands_per_octave_warped) {
161#else
162            if (*in >= *out * lim_bands_per_octave_warped) {
163#endif /* USE_FIXED */
164                *++out = *in++;
165            } else if (*in == *out ||
166                !in_table_int16(patch_borders, sbr->num_patches, *in)) {
167                in++;
168                sbr->n_lim--;
169            } else if (!in_table_int16(patch_borders, sbr->num_patches, *out)) {
170                *out = *in++;
171                sbr->n_lim--;
172            } else {
173                *++out = *in++;
174            }
175        }
176    } else {
177        sbr->f_tablelim[0] = sbr->f_tablelow[0];
178        sbr->f_tablelim[1] = sbr->f_tablelow[sbr->n[0]];
179        sbr->n_lim = 1;
180    }
181}
182
183static unsigned int read_sbr_header(SpectralBandReplication *sbr, GetBitContext *gb)
184{
185    unsigned int cnt = get_bits_count(gb);
186    uint8_t bs_header_extra_1;
187    uint8_t bs_header_extra_2;
188    int old_bs_limiter_bands = sbr->bs_limiter_bands;
189    SpectrumParameters old_spectrum_params;
190
191    sbr->start = 1;
192    sbr->ready_for_dequant = 0;
193
194    // Save last spectrum parameters variables to compare to new ones
195    memcpy(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters));
196
197    sbr->bs_amp_res_header              = get_bits1(gb);
198    sbr->spectrum_params.bs_start_freq  = get_bits(gb, 4);
199    sbr->spectrum_params.bs_stop_freq   = get_bits(gb, 4);
200    sbr->spectrum_params.bs_xover_band  = get_bits(gb, 3);
201                                          skip_bits(gb, 2); // bs_reserved
202
203    bs_header_extra_1 = get_bits1(gb);
204    bs_header_extra_2 = get_bits1(gb);
205
206    if (bs_header_extra_1) {
207        sbr->spectrum_params.bs_freq_scale  = get_bits(gb, 2);
208        sbr->spectrum_params.bs_alter_scale = get_bits1(gb);
209        sbr->spectrum_params.bs_noise_bands = get_bits(gb, 2);
210    } else {
211        sbr->spectrum_params.bs_freq_scale  = 2;
212        sbr->spectrum_params.bs_alter_scale = 1;
213        sbr->spectrum_params.bs_noise_bands = 2;
214    }
215
216    // Check if spectrum parameters changed
217    if (memcmp(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters)))
218        sbr->reset = 1;
219
220    if (bs_header_extra_2) {
221        sbr->bs_limiter_bands  = get_bits(gb, 2);
222        sbr->bs_limiter_gains  = get_bits(gb, 2);
223        sbr->bs_interpol_freq  = get_bits1(gb);
224        sbr->bs_smoothing_mode = get_bits1(gb);
225    } else {
226        sbr->bs_limiter_bands  = 2;
227        sbr->bs_limiter_gains  = 2;
228        sbr->bs_interpol_freq  = 1;
229        sbr->bs_smoothing_mode = 1;
230    }
231
232    if (sbr->bs_limiter_bands != old_bs_limiter_bands && !sbr->reset)
233        sbr_make_f_tablelim(sbr);
234
235    return get_bits_count(gb) - cnt;
236}
237
238static int array_min_int16(const int16_t *array, int nel)
239{
240    int i, min = array[0];
241    for (i = 1; i < nel; i++)
242        min = FFMIN(array[i], min);
243    return min;
244}
245
246static int check_n_master(AVCodecContext *avctx, int n_master, int bs_xover_band)
247{
248    // Requirements (14496-3 sp04 p205)
249    if (n_master <= 0) {
250        av_log(avctx, AV_LOG_ERROR, "Invalid n_master: %d\n", n_master);
251        return -1;
252    }
253    if (bs_xover_band >= n_master) {
254        av_log(avctx, AV_LOG_ERROR,
255               "Invalid bitstream, crossover band index beyond array bounds: %d\n",
256               bs_xover_band);
257        return -1;
258    }
259    return 0;
260}
261
262/// Master Frequency Band Table (14496-3 sp04 p194)
263static int sbr_make_f_master(AACContext *ac, SpectralBandReplication *sbr,
264                             SpectrumParameters *spectrum)
265{
266    unsigned int temp, max_qmf_subbands = 0;
267    unsigned int start_min, stop_min;
268    int k;
269    const int8_t *sbr_offset_ptr;
270    int16_t stop_dk[13];
271
272    switch (sbr->sample_rate) {
273    case 16000:
274        sbr_offset_ptr = sbr_offset[0];
275        break;
276    case 22050:
277        sbr_offset_ptr = sbr_offset[1];
278        break;
279    case 24000:
280        sbr_offset_ptr = sbr_offset[2];
281        break;
282    case 32000:
283        sbr_offset_ptr = sbr_offset[3];
284        break;
285    case 44100: case 48000: case 64000:
286        sbr_offset_ptr = sbr_offset[4];
287        break;
288    case 88200: case 96000: case 128000: case 176400: case 192000:
289        sbr_offset_ptr = sbr_offset[5];
290        break;
291    default:
292        av_log(ac->avctx, AV_LOG_ERROR,
293               "Unsupported sample rate for SBR: %d\n", sbr->sample_rate);
294        return -1;
295    }
296
297    if (sbr->sample_rate < 32000) {
298        temp = 3000;
299    } else if (sbr->sample_rate < 64000) {
300        temp = 4000;
301    } else
302        temp = 5000;
303
304    start_min = ((temp << 7) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
305    stop_min  = ((temp << 8) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
306
307    sbr->k[0] = start_min + sbr_offset_ptr[spectrum->bs_start_freq];
308
309    if (spectrum->bs_stop_freq < 14) {
310        sbr->k[2] = stop_min;
311        make_bands(stop_dk, stop_min, 64, 13);
312        AV_QSORT(stop_dk, 13, int16_t, qsort_comparison_function_int16);
313        for (k = 0; k < spectrum->bs_stop_freq; k++)
314            sbr->k[2] += stop_dk[k];
315    } else if (spectrum->bs_stop_freq == 14) {
316        sbr->k[2] = 2*sbr->k[0];
317    } else if (spectrum->bs_stop_freq == 15) {
318        sbr->k[2] = 3*sbr->k[0];
319    } else {
320        av_log(ac->avctx, AV_LOG_ERROR,
321               "Invalid bs_stop_freq: %d\n", spectrum->bs_stop_freq);
322        return -1;
323    }
324    sbr->k[2] = FFMIN(64, sbr->k[2]);
325
326    // Requirements (14496-3 sp04 p205)
327    if (sbr->sample_rate <= 32000) {
328        max_qmf_subbands = 48;
329    } else if (sbr->sample_rate == 44100) {
330        max_qmf_subbands = 35;
331    } else if (sbr->sample_rate >= 48000)
332        max_qmf_subbands = 32;
333    else
334        av_assert0(0);
335
336    if (sbr->k[2] - sbr->k[0] > max_qmf_subbands) {
337        av_log(ac->avctx, AV_LOG_ERROR,
338               "Invalid bitstream, too many QMF subbands: %d\n", sbr->k[2] - sbr->k[0]);
339        return -1;
340    }
341
342    if (!spectrum->bs_freq_scale) {
343        int dk, k2diff;
344
345        dk = spectrum->bs_alter_scale + 1;
346        sbr->n_master = ((sbr->k[2] - sbr->k[0] + (dk&2)) >> dk) << 1;
347        if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
348            return -1;
349
350        for (k = 1; k <= sbr->n_master; k++)
351            sbr->f_master[k] = dk;
352
353        k2diff = sbr->k[2] - sbr->k[0] - sbr->n_master * dk;
354        if (k2diff < 0) {
355            sbr->f_master[1]--;
356            sbr->f_master[2]-= (k2diff < -1);
357        } else if (k2diff) {
358            sbr->f_master[sbr->n_master]++;
359        }
360
361        sbr->f_master[0] = sbr->k[0];
362        for (k = 1; k <= sbr->n_master; k++)
363            sbr->f_master[k] += sbr->f_master[k - 1];
364
365    } else {
366        int half_bands = 7 - spectrum->bs_freq_scale;      // bs_freq_scale  = {1,2,3}
367        int two_regions, num_bands_0;
368        int vdk0_max, vdk1_min;
369        int16_t vk0[49];
370#if USE_FIXED
371        int tmp, nz = 0;
372#endif /* USE_FIXED */
373
374        if (49 * sbr->k[2] > 110 * sbr->k[0]) {
375            two_regions = 1;
376            sbr->k[1] = 2 * sbr->k[0];
377        } else {
378            two_regions = 0;
379            sbr->k[1] = sbr->k[2];
380        }
381
382#if USE_FIXED
383        tmp = (sbr->k[1] << 23) / sbr->k[0];
384        while (tmp < 0x40000000) {
385          tmp <<= 1;
386          nz++;
387        }
388        tmp = fixed_log(tmp - 0x80000000);
389        tmp = (int)(((int64_t)tmp * CONST_RECIP_LN2 + 0x20000000) >> 30);
390        tmp = (((tmp + 0x80) >> 8) + ((8 - nz) << 23)) * half_bands;
391        num_bands_0 = ((tmp + 0x400000) >> 23) * 2;
392#else
393        num_bands_0 = lrintf(half_bands * log2f(sbr->k[1] / (float)sbr->k[0])) * 2;
394#endif /* USE_FIXED */
395
396        if (num_bands_0 <= 0) { // Requirements (14496-3 sp04 p205)
397            av_log(ac->avctx, AV_LOG_ERROR, "Invalid num_bands_0: %d\n", num_bands_0);
398            return -1;
399        }
400
401        vk0[0] = 0;
402
403        make_bands(vk0+1, sbr->k[0], sbr->k[1], num_bands_0);
404
405        AV_QSORT(vk0 + 1, num_bands_0, int16_t, qsort_comparison_function_int16);
406        vdk0_max = vk0[num_bands_0];
407
408        vk0[0] = sbr->k[0];
409        for (k = 1; k <= num_bands_0; k++) {
410            if (vk0[k] <= 0) { // Requirements (14496-3 sp04 p205)
411                av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk0[%d]: %d\n", k, vk0[k]);
412                return -1;
413            }
414            vk0[k] += vk0[k-1];
415        }
416
417        if (two_regions) {
418            int16_t vk1[49];
419#if USE_FIXED
420            int num_bands_1;
421
422            tmp = (sbr->k[2] << 23) / sbr->k[1];
423            nz = 0;
424            while (tmp < 0x40000000) {
425              tmp <<= 1;
426              nz++;
427            }
428            tmp = fixed_log(tmp - 0x80000000);
429            tmp = (int)(((int64_t)tmp * CONST_RECIP_LN2 + 0x20000000) >> 30);
430            tmp = (((tmp + 0x80) >> 8) + ((8 - nz) << 23)) * half_bands;
431            if (spectrum->bs_alter_scale)
432                tmp = (int)(((int64_t)tmp * CONST_076923 + 0x40000000) >> 31);
433            num_bands_1 = ((tmp + 0x400000) >> 23) * 2;
434#else
435            float invwarp = spectrum->bs_alter_scale ? 0.76923076923076923077f
436                                                     : 1.0f; // bs_alter_scale = {0,1}
437            int num_bands_1 = lrintf(half_bands * invwarp *
438                                     log2f(sbr->k[2] / (float)sbr->k[1])) * 2;
439#endif /* USE_FIXED */
440            make_bands(vk1+1, sbr->k[1], sbr->k[2], num_bands_1);
441
442            vdk1_min = array_min_int16(vk1 + 1, num_bands_1);
443
444            if (vdk1_min < vdk0_max) {
445                int change;
446                AV_QSORT(vk1 + 1, num_bands_1, int16_t, qsort_comparison_function_int16);
447                change = FFMIN(vdk0_max - vk1[1], (vk1[num_bands_1] - vk1[1]) >> 1);
448                vk1[1]           += change;
449                vk1[num_bands_1] -= change;
450            }
451
452            AV_QSORT(vk1 + 1, num_bands_1, int16_t, qsort_comparison_function_int16);
453
454            vk1[0] = sbr->k[1];
455            for (k = 1; k <= num_bands_1; k++) {
456                if (vk1[k] <= 0) { // Requirements (14496-3 sp04 p205)
457                    av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk1[%d]: %d\n", k, vk1[k]);
458                    return -1;
459                }
460                vk1[k] += vk1[k-1];
461            }
462
463            sbr->n_master = num_bands_0 + num_bands_1;
464            if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
465                return -1;
466            memcpy(&sbr->f_master[0],               vk0,
467                   (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
468            memcpy(&sbr->f_master[num_bands_0 + 1], vk1 + 1,
469                    num_bands_1      * sizeof(sbr->f_master[0]));
470
471        } else {
472            sbr->n_master = num_bands_0;
473            if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
474                return -1;
475            memcpy(sbr->f_master, vk0, (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
476        }
477    }
478
479    return 0;
480}
481
482/// High Frequency Generation - Patch Construction (14496-3 sp04 p216 fig. 4.46)
483static int sbr_hf_calc_npatches(AACContext *ac, SpectralBandReplication *sbr)
484{
485    int i, k, last_k = -1, last_msb = -1, sb = 0;
486    int msb = sbr->k[0];
487    int usb = sbr->kx[1];
488    int goal_sb = ((1000 << 11) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
489
490    sbr->num_patches = 0;
491
492    if (goal_sb < sbr->kx[1] + sbr->m[1]) {
493        for (k = 0; sbr->f_master[k] < goal_sb; k++) ;
494    } else
495        k = sbr->n_master;
496
497    do {
498        int odd = 0;
499        if (k == last_k && msb == last_msb) {
500            av_log(ac->avctx, AV_LOG_ERROR, "patch construction failed\n");
501            return AVERROR_INVALIDDATA;
502        }
503        last_k = k;
504        last_msb = msb;
505        for (i = k; i == k || sb > (sbr->k[0] - 1 + msb - odd); i--) {
506            sb = sbr->f_master[i];
507            odd = (sb + sbr->k[0]) & 1;
508        }
509
510        // Requirements (14496-3 sp04 p205) sets the maximum number of patches to 5.
511        // After this check the final number of patches can still be six which is
512        // illegal however the Coding Technologies decoder check stream has a final
513        // count of 6 patches
514        if (sbr->num_patches > 5) {
515            av_log(ac->avctx, AV_LOG_ERROR, "Too many patches: %d\n", sbr->num_patches);
516            return -1;
517        }
518
519        sbr->patch_num_subbands[sbr->num_patches]  = FFMAX(sb - usb, 0);
520        sbr->patch_start_subband[sbr->num_patches] = sbr->k[0] - odd - sbr->patch_num_subbands[sbr->num_patches];
521
522        if (sbr->patch_num_subbands[sbr->num_patches] > 0) {
523            usb = sb;
524            msb = sb;
525            sbr->num_patches++;
526        } else
527            msb = sbr->kx[1];
528
529        if (sbr->f_master[k] - sb < 3)
530            k = sbr->n_master;
531    } while (sb != sbr->kx[1] + sbr->m[1]);
532
533    if (sbr->num_patches > 1 &&
534        sbr->patch_num_subbands[sbr->num_patches - 1] < 3)
535        sbr->num_patches--;
536
537    return 0;
538}
539
540/// Derived Frequency Band Tables (14496-3 sp04 p197)
541static int sbr_make_f_derived(AACContext *ac, SpectralBandReplication *sbr)
542{
543    int k, temp;
544#if USE_FIXED
545    int nz = 0;
546#endif /* USE_FIXED */
547
548    sbr->n[1] = sbr->n_master - sbr->spectrum_params.bs_xover_band;
549    sbr->n[0] = (sbr->n[1] + 1) >> 1;
550
551    memcpy(sbr->f_tablehigh, &sbr->f_master[sbr->spectrum_params.bs_xover_band],
552           (sbr->n[1] + 1) * sizeof(sbr->f_master[0]));
553    sbr->m[1] = sbr->f_tablehigh[sbr->n[1]] - sbr->f_tablehigh[0];
554    sbr->kx[1] = sbr->f_tablehigh[0];
555
556    // Requirements (14496-3 sp04 p205)
557    if (sbr->kx[1] + sbr->m[1] > 64) {
558        av_log(ac->avctx, AV_LOG_ERROR,
559               "Stop frequency border too high: %d\n", sbr->kx[1] + sbr->m[1]);
560        return -1;
561    }
562    if (sbr->kx[1] > 32) {
563        av_log(ac->avctx, AV_LOG_ERROR, "Start frequency border too high: %d\n", sbr->kx[1]);
564        return -1;
565    }
566
567    sbr->f_tablelow[0] = sbr->f_tablehigh[0];
568    temp = sbr->n[1] & 1;
569    for (k = 1; k <= sbr->n[0]; k++)
570        sbr->f_tablelow[k] = sbr->f_tablehigh[2 * k - temp];
571#if USE_FIXED
572    temp = (sbr->k[2] << 23) / sbr->kx[1];
573    while (temp < 0x40000000) {
574        temp <<= 1;
575        nz++;
576    }
577    temp = fixed_log(temp - 0x80000000);
578    temp = (int)(((int64_t)temp * CONST_RECIP_LN2 + 0x20000000) >> 30);
579    temp = (((temp + 0x80) >> 8) + ((8 - nz) << 23)) * sbr->spectrum_params.bs_noise_bands;
580
581    sbr->n_q = (temp + 0x400000) >> 23;
582    if (sbr->n_q < 1)
583        sbr->n_q = 1;
584#else
585    sbr->n_q = FFMAX(1, lrintf(sbr->spectrum_params.bs_noise_bands *
586                               log2f(sbr->k[2] / (float)sbr->kx[1]))); // 0 <= bs_noise_bands <= 3
587#endif /* USE_FIXED */
588
589    if (sbr->n_q > 5) {
590        av_log(ac->avctx, AV_LOG_ERROR, "Too many noise floor scale factors: %d\n", sbr->n_q);
591        return -1;
592    }
593
594    sbr->f_tablenoise[0] = sbr->f_tablelow[0];
595    temp = 0;
596    for (k = 1; k <= sbr->n_q; k++) {
597        temp += (sbr->n[0] - temp) / (sbr->n_q + 1 - k);
598        sbr->f_tablenoise[k] = sbr->f_tablelow[temp];
599    }
600
601    if (sbr_hf_calc_npatches(ac, sbr) < 0)
602        return -1;
603
604    sbr_make_f_tablelim(sbr);
605
606    sbr->data[0].f_indexnoise = 0;
607    sbr->data[1].f_indexnoise = 0;
608
609    return 0;
610}
611
612static av_always_inline void get_bits1_vector(GetBitContext *gb, uint8_t *vec,
613                                              int elements)
614{
615    int i;
616    for (i = 0; i < elements; i++) {
617        vec[i] = get_bits1(gb);
618    }
619}
620
621/** ceil(log2(index+1)) */
622static const int8_t ceil_log2[] = {
623    0, 1, 2, 2, 3, 3,
624};
625
626static int read_sbr_grid(AACContext *ac, SpectralBandReplication *sbr,
627                         GetBitContext *gb, SBRData *ch_data)
628{
629    int i;
630    int bs_pointer = 0;
631    // frameLengthFlag ? 15 : 16; 960 sample length frames unsupported; this value is numTimeSlots
632    int abs_bord_trail = 16;
633    int num_rel_lead, num_rel_trail;
634    unsigned bs_num_env_old = ch_data->bs_num_env;
635    int bs_frame_class, bs_num_env;
636
637    ch_data->bs_freq_res[0] = ch_data->bs_freq_res[ch_data->bs_num_env];
638    ch_data->bs_amp_res = sbr->bs_amp_res_header;
639    ch_data->t_env_num_env_old = ch_data->t_env[bs_num_env_old];
640
641    switch (bs_frame_class = get_bits(gb, 2)) {
642    case FIXFIX:
643        bs_num_env = 1 << get_bits(gb, 2);
644        if (bs_num_env > 4) {
645            av_log(ac->avctx, AV_LOG_ERROR,
646                   "Invalid bitstream, too many SBR envelopes in FIXFIX type SBR frame: %d\n",
647                   bs_num_env);
648            return -1;
649        }
650        ch_data->bs_num_env = bs_num_env;
651        num_rel_lead                        = ch_data->bs_num_env - 1;
652        if (ch_data->bs_num_env == 1)
653            ch_data->bs_amp_res = 0;
654
655
656        ch_data->t_env[0]                   = 0;
657        ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
658
659        abs_bord_trail = (abs_bord_trail + (ch_data->bs_num_env >> 1)) /
660                   ch_data->bs_num_env;
661        for (i = 0; i < num_rel_lead; i++)
662            ch_data->t_env[i + 1] = ch_data->t_env[i] + abs_bord_trail;
663
664        ch_data->bs_freq_res[1] = get_bits1(gb);
665        for (i = 1; i < ch_data->bs_num_env; i++)
666            ch_data->bs_freq_res[i + 1] = ch_data->bs_freq_res[1];
667        break;
668    case FIXVAR:
669        abs_bord_trail                     += get_bits(gb, 2);
670        num_rel_trail                       = get_bits(gb, 2);
671        ch_data->bs_num_env                 = num_rel_trail + 1;
672        ch_data->t_env[0]                   = 0;
673        ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
674
675        for (i = 0; i < num_rel_trail; i++)
676            ch_data->t_env[ch_data->bs_num_env - 1 - i] =
677                ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
678
679        bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
680
681        for (i = 0; i < ch_data->bs_num_env; i++)
682            ch_data->bs_freq_res[ch_data->bs_num_env - i] = get_bits1(gb);
683        break;
684    case VARFIX:
685        ch_data->t_env[0]                   = get_bits(gb, 2);
686        num_rel_lead                        = get_bits(gb, 2);
687        ch_data->bs_num_env                 = num_rel_lead + 1;
688        ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
689
690        for (i = 0; i < num_rel_lead; i++)
691            ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
692
693        bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
694
695        get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
696        break;
697    case VARVAR:
698        ch_data->t_env[0]                   = get_bits(gb, 2);
699        abs_bord_trail                     += get_bits(gb, 2);
700        num_rel_lead                        = get_bits(gb, 2);
701        num_rel_trail                       = get_bits(gb, 2);
702        bs_num_env                          = num_rel_lead + num_rel_trail + 1;
703
704        if (bs_num_env > 5) {
705            av_log(ac->avctx, AV_LOG_ERROR,
706                   "Invalid bitstream, too many SBR envelopes in VARVAR type SBR frame: %d\n",
707                   bs_num_env);
708            return -1;
709        }
710        ch_data->bs_num_env = bs_num_env;
711
712        ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
713
714        for (i = 0; i < num_rel_lead; i++)
715            ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
716        for (i = 0; i < num_rel_trail; i++)
717            ch_data->t_env[ch_data->bs_num_env - 1 - i] =
718                ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
719
720        bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
721
722        get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
723        break;
724    }
725    ch_data->bs_frame_class = bs_frame_class;
726
727    av_assert0(bs_pointer >= 0);
728    if (bs_pointer > ch_data->bs_num_env + 1) {
729        av_log(ac->avctx, AV_LOG_ERROR,
730               "Invalid bitstream, bs_pointer points to a middle noise border outside the time borders table: %d\n",
731               bs_pointer);
732        return -1;
733    }
734
735    for (i = 1; i <= ch_data->bs_num_env; i++) {
736        if (ch_data->t_env[i-1] >= ch_data->t_env[i]) {
737            av_log(ac->avctx, AV_LOG_ERROR, "Not strictly monotone time borders\n");
738            return -1;
739        }
740    }
741
742    ch_data->bs_num_noise = (ch_data->bs_num_env > 1) + 1;
743
744    ch_data->t_q[0]                     = ch_data->t_env[0];
745    ch_data->t_q[ch_data->bs_num_noise] = ch_data->t_env[ch_data->bs_num_env];
746    if (ch_data->bs_num_noise > 1) {
747        int idx;
748        if (ch_data->bs_frame_class == FIXFIX) {
749            idx = ch_data->bs_num_env >> 1;
750        } else if (ch_data->bs_frame_class & 1) { // FIXVAR or VARVAR
751            idx = ch_data->bs_num_env - FFMAX(bs_pointer - 1, 1);
752        } else { // VARFIX
753            if (!bs_pointer)
754                idx = 1;
755            else if (bs_pointer == 1)
756                idx = ch_data->bs_num_env - 1;
757            else // bs_pointer > 1
758                idx = bs_pointer - 1;
759        }
760        ch_data->t_q[1] = ch_data->t_env[idx];
761    }
762
763    ch_data->e_a[0] = -(ch_data->e_a[1] != bs_num_env_old); // l_APrev
764    ch_data->e_a[1] = -1;
765    if ((ch_data->bs_frame_class & 1) && bs_pointer) { // FIXVAR or VARVAR and bs_pointer != 0
766        ch_data->e_a[1] = ch_data->bs_num_env + 1 - bs_pointer;
767    } else if ((ch_data->bs_frame_class == 2) && (bs_pointer > 1)) // VARFIX and bs_pointer > 1
768        ch_data->e_a[1] = bs_pointer - 1;
769
770    return 0;
771}
772
773static void copy_sbr_grid(SBRData *dst, const SBRData *src) {
774    //These variables are saved from the previous frame rather than copied
775    dst->bs_freq_res[0]    = dst->bs_freq_res[dst->bs_num_env];
776    dst->t_env_num_env_old = dst->t_env[dst->bs_num_env];
777    dst->e_a[0]            = -(dst->e_a[1] != dst->bs_num_env);
778
779    //These variables are read from the bitstream and therefore copied
780    memcpy(dst->bs_freq_res+1, src->bs_freq_res+1, sizeof(dst->bs_freq_res)-sizeof(*dst->bs_freq_res));
781    memcpy(dst->t_env,         src->t_env,         sizeof(dst->t_env));
782    memcpy(dst->t_q,           src->t_q,           sizeof(dst->t_q));
783    dst->bs_num_env        = src->bs_num_env;
784    dst->bs_amp_res        = src->bs_amp_res;
785    dst->bs_num_noise      = src->bs_num_noise;
786    dst->bs_frame_class    = src->bs_frame_class;
787    dst->e_a[1]            = src->e_a[1];
788}
789
790/// Read how the envelope and noise floor data is delta coded
791static void read_sbr_dtdf(SpectralBandReplication *sbr, GetBitContext *gb,
792                          SBRData *ch_data)
793{
794    get_bits1_vector(gb, ch_data->bs_df_env,   ch_data->bs_num_env);
795    get_bits1_vector(gb, ch_data->bs_df_noise, ch_data->bs_num_noise);
796}
797
798/// Read inverse filtering data
799static void read_sbr_invf(SpectralBandReplication *sbr, GetBitContext *gb,
800                          SBRData *ch_data)
801{
802    int i;
803
804    memcpy(ch_data->bs_invf_mode[1], ch_data->bs_invf_mode[0], 5 * sizeof(uint8_t));
805    for (i = 0; i < sbr->n_q; i++)
806        ch_data->bs_invf_mode[0][i] = get_bits(gb, 2);
807}
808
809static int read_sbr_envelope(AACContext *ac, SpectralBandReplication *sbr, GetBitContext *gb,
810                              SBRData *ch_data, int ch)
811{
812    int bits;
813    int i, j, k;
814    const VLCElem *t_huff, *f_huff;
815    int t_lav, f_lav;
816    const int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
817    const int odd = sbr->n[1] & 1;
818
819    if (sbr->bs_coupling && ch) {
820        if (ch_data->bs_amp_res) {
821            bits   = 5;
822            t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_3_0DB].table;
823            t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_3_0DB];
824            f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
825            f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
826        } else {
827            bits   = 6;
828            t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_1_5DB].table;
829            t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_1_5DB];
830            f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_1_5DB].table;
831            f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_1_5DB];
832        }
833    } else {
834        if (ch_data->bs_amp_res) {
835            bits   = 6;
836            t_huff = vlc_sbr[T_HUFFMAN_ENV_3_0DB].table;
837            t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_3_0DB];
838            f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
839            f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
840        } else {
841            bits   = 7;
842            t_huff = vlc_sbr[T_HUFFMAN_ENV_1_5DB].table;
843            t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_1_5DB];
844            f_huff = vlc_sbr[F_HUFFMAN_ENV_1_5DB].table;
845            f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_1_5DB];
846        }
847    }
848
849    for (i = 0; i < ch_data->bs_num_env; i++) {
850        if (ch_data->bs_df_env[i]) {
851            // bs_freq_res[0] == bs_freq_res[bs_num_env] from prev frame
852            if (ch_data->bs_freq_res[i + 1] == ch_data->bs_freq_res[i]) {
853                for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
854                    ch_data->env_facs_q[i + 1][j] = ch_data->env_facs_q[i][j] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
855                    if (ch_data->env_facs_q[i + 1][j] > 127U) {
856                        av_log(ac->avctx, AV_LOG_ERROR, "env_facs_q %d is invalid\n", ch_data->env_facs_q[i + 1][j]);
857                        return AVERROR_INVALIDDATA;
858                    }
859                }
860            } else if (ch_data->bs_freq_res[i + 1]) {
861                for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
862                    k = (j + odd) >> 1; // find k such that f_tablelow[k] <= f_tablehigh[j] < f_tablelow[k + 1]
863                    ch_data->env_facs_q[i + 1][j] = ch_data->env_facs_q[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
864                    if (ch_data->env_facs_q[i + 1][j] > 127U) {
865                        av_log(ac->avctx, AV_LOG_ERROR, "env_facs_q %d is invalid\n", ch_data->env_facs_q[i + 1][j]);
866                        return AVERROR_INVALIDDATA;
867                    }
868                }
869            } else {
870                for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
871                    k = j ? 2*j - odd : 0; // find k such that f_tablehigh[k] == f_tablelow[j]
872                    ch_data->env_facs_q[i + 1][j] = ch_data->env_facs_q[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
873                    if (ch_data->env_facs_q[i + 1][j] > 127U) {
874                        av_log(ac->avctx, AV_LOG_ERROR, "env_facs_q %d is invalid\n", ch_data->env_facs_q[i + 1][j]);
875                        return AVERROR_INVALIDDATA;
876                    }
877                }
878            }
879        } else {
880            ch_data->env_facs_q[i + 1][0] = delta * get_bits(gb, bits); // bs_env_start_value_balance
881            for (j = 1; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
882                ch_data->env_facs_q[i + 1][j] = ch_data->env_facs_q[i + 1][j - 1] + delta * (get_vlc2(gb, f_huff, 9, 3) - f_lav);
883                if (ch_data->env_facs_q[i + 1][j] > 127U) {
884                    av_log(ac->avctx, AV_LOG_ERROR, "env_facs_q %d is invalid\n", ch_data->env_facs_q[i + 1][j]);
885                    return AVERROR_INVALIDDATA;
886                }
887            }
888        }
889    }
890
891    //assign 0th elements of env_facs_q from last elements
892    memcpy(ch_data->env_facs_q[0], ch_data->env_facs_q[ch_data->bs_num_env],
893           sizeof(ch_data->env_facs_q[0]));
894
895    return 0;
896}
897
898static int read_sbr_noise(AACContext *ac, SpectralBandReplication *sbr, GetBitContext *gb,
899                           SBRData *ch_data, int ch)
900{
901    int i, j;
902    const VLCElem *t_huff, *f_huff;
903    int t_lav, f_lav;
904    int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
905
906    if (sbr->bs_coupling && ch) {
907        t_huff = vlc_sbr[T_HUFFMAN_NOISE_BAL_3_0DB].table;
908        t_lav  = vlc_sbr_lav[T_HUFFMAN_NOISE_BAL_3_0DB];
909        f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
910        f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
911    } else {
912        t_huff = vlc_sbr[T_HUFFMAN_NOISE_3_0DB].table;
913        t_lav  = vlc_sbr_lav[T_HUFFMAN_NOISE_3_0DB];
914        f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
915        f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
916    }
917
918    for (i = 0; i < ch_data->bs_num_noise; i++) {
919        if (ch_data->bs_df_noise[i]) {
920            for (j = 0; j < sbr->n_q; j++) {
921                ch_data->noise_facs_q[i + 1][j] = ch_data->noise_facs_q[i][j] + delta * (get_vlc2(gb, t_huff, 9, 2) - t_lav);
922                if (ch_data->noise_facs_q[i + 1][j] > 30U) {
923                    av_log(ac->avctx, AV_LOG_ERROR, "noise_facs_q %d is invalid\n", ch_data->noise_facs_q[i + 1][j]);
924                    return AVERROR_INVALIDDATA;
925                }
926            }
927        } else {
928            ch_data->noise_facs_q[i + 1][0] = delta * get_bits(gb, 5); // bs_noise_start_value_balance or bs_noise_start_value_level
929            for (j = 1; j < sbr->n_q; j++) {
930                ch_data->noise_facs_q[i + 1][j] = ch_data->noise_facs_q[i + 1][j - 1] + delta * (get_vlc2(gb, f_huff, 9, 3) - f_lav);
931                if (ch_data->noise_facs_q[i + 1][j] > 30U) {
932                    av_log(ac->avctx, AV_LOG_ERROR, "noise_facs_q %d is invalid\n", ch_data->noise_facs_q[i + 1][j]);
933                    return AVERROR_INVALIDDATA;
934                }
935            }
936        }
937    }
938
939    //assign 0th elements of noise_facs_q from last elements
940    memcpy(ch_data->noise_facs_q[0], ch_data->noise_facs_q[ch_data->bs_num_noise],
941           sizeof(ch_data->noise_facs_q[0]));
942    return 0;
943}
944
945static void read_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
946                               GetBitContext *gb,
947                               int bs_extension_id, int *num_bits_left)
948{
949    switch (bs_extension_id) {
950    case EXTENSION_ID_PS:
951        if (!ac->oc[1].m4ac.ps) {
952            av_log(ac->avctx, AV_LOG_ERROR, "Parametric Stereo signaled to be not-present but was found in the bitstream.\n");
953            skip_bits_long(gb, *num_bits_left); // bs_fill_bits
954            *num_bits_left = 0;
955        } else {
956            *num_bits_left -= ff_ps_read_data(ac->avctx, gb, &sbr->ps.common, *num_bits_left);
957            ac->avctx->profile = FF_PROFILE_AAC_HE_V2;
958        }
959        break;
960    default:
961        // some files contain 0-padding
962        if (bs_extension_id || *num_bits_left > 16 || show_bits(gb, *num_bits_left))
963            avpriv_request_sample(ac->avctx, "Reserved SBR extensions");
964        skip_bits_long(gb, *num_bits_left); // bs_fill_bits
965        *num_bits_left = 0;
966        break;
967    }
968}
969
970static int read_sbr_single_channel_element(AACContext *ac,
971                                            SpectralBandReplication *sbr,
972                                            GetBitContext *gb)
973{
974    int ret;
975
976    if (get_bits1(gb)) // bs_data_extra
977        skip_bits(gb, 4); // bs_reserved
978
979    if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
980        return -1;
981    read_sbr_dtdf(sbr, gb, &sbr->data[0]);
982    read_sbr_invf(sbr, gb, &sbr->data[0]);
983    if((ret = read_sbr_envelope(ac, sbr, gb, &sbr->data[0], 0)) < 0)
984        return ret;
985    if((ret = read_sbr_noise(ac, sbr, gb, &sbr->data[0], 0)) < 0)
986        return ret;
987
988    if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
989        get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
990
991    return 0;
992}
993
994static int read_sbr_channel_pair_element(AACContext *ac,
995                                          SpectralBandReplication *sbr,
996                                          GetBitContext *gb)
997{
998    int ret;
999
1000    if (get_bits1(gb))    // bs_data_extra
1001        skip_bits(gb, 8); // bs_reserved
1002
1003    if ((sbr->bs_coupling = get_bits1(gb))) {
1004        if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
1005            return -1;
1006        copy_sbr_grid(&sbr->data[1], &sbr->data[0]);
1007        read_sbr_dtdf(sbr, gb, &sbr->data[0]);
1008        read_sbr_dtdf(sbr, gb, &sbr->data[1]);
1009        read_sbr_invf(sbr, gb, &sbr->data[0]);
1010        memcpy(sbr->data[1].bs_invf_mode[1], sbr->data[1].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
1011        memcpy(sbr->data[1].bs_invf_mode[0], sbr->data[0].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
1012        if((ret = read_sbr_envelope(ac, sbr, gb, &sbr->data[0], 0)) < 0)
1013            return ret;
1014        if((ret = read_sbr_noise(ac, sbr, gb, &sbr->data[0], 0)) < 0)
1015            return ret;
1016        if((ret = read_sbr_envelope(ac, sbr, gb, &sbr->data[1], 1)) < 0)
1017            return ret;
1018        if((ret = read_sbr_noise(ac, sbr, gb, &sbr->data[1], 1)) < 0)
1019            return ret;
1020    } else {
1021        if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]) ||
1022            read_sbr_grid(ac, sbr, gb, &sbr->data[1]))
1023            return -1;
1024        read_sbr_dtdf(sbr, gb, &sbr->data[0]);
1025        read_sbr_dtdf(sbr, gb, &sbr->data[1]);
1026        read_sbr_invf(sbr, gb, &sbr->data[0]);
1027        read_sbr_invf(sbr, gb, &sbr->data[1]);
1028        if((ret = read_sbr_envelope(ac, sbr, gb, &sbr->data[0], 0)) < 0)
1029            return ret;
1030        if((ret = read_sbr_envelope(ac, sbr, gb, &sbr->data[1], 1)) < 0)
1031            return ret;
1032        if((ret = read_sbr_noise(ac, sbr, gb, &sbr->data[0], 0)) < 0)
1033            return ret;
1034        if((ret = read_sbr_noise(ac, sbr, gb, &sbr->data[1], 1)) < 0)
1035            return ret;
1036    }
1037
1038    if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
1039        get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
1040    if ((sbr->data[1].bs_add_harmonic_flag = get_bits1(gb)))
1041        get_bits1_vector(gb, sbr->data[1].bs_add_harmonic, sbr->n[1]);
1042
1043    return 0;
1044}
1045
1046static unsigned int read_sbr_data(AACContext *ac, SpectralBandReplication *sbr,
1047                                  GetBitContext *gb, int id_aac)
1048{
1049    unsigned int cnt = get_bits_count(gb);
1050
1051    sbr->id_aac = id_aac;
1052    sbr->ready_for_dequant = 1;
1053
1054    if (id_aac == TYPE_SCE || id_aac == TYPE_CCE) {
1055        if (read_sbr_single_channel_element(ac, sbr, gb)) {
1056            sbr_turnoff(sbr);
1057            return get_bits_count(gb) - cnt;
1058        }
1059    } else if (id_aac == TYPE_CPE) {
1060        if (read_sbr_channel_pair_element(ac, sbr, gb)) {
1061            sbr_turnoff(sbr);
1062            return get_bits_count(gb) - cnt;
1063        }
1064    } else {
1065        av_log(ac->avctx, AV_LOG_ERROR,
1066            "Invalid bitstream - cannot apply SBR to element type %d\n", id_aac);
1067        sbr_turnoff(sbr);
1068        return get_bits_count(gb) - cnt;
1069    }
1070    if (get_bits1(gb)) { // bs_extended_data
1071        int num_bits_left = get_bits(gb, 4); // bs_extension_size
1072        if (num_bits_left == 15)
1073            num_bits_left += get_bits(gb, 8); // bs_esc_count
1074
1075        num_bits_left <<= 3;
1076        while (num_bits_left > 7) {
1077            num_bits_left -= 2;
1078            read_sbr_extension(ac, sbr, gb, get_bits(gb, 2), &num_bits_left); // bs_extension_id
1079        }
1080        if (num_bits_left < 0) {
1081            av_log(ac->avctx, AV_LOG_ERROR, "SBR Extension over read.\n");
1082        }
1083        if (num_bits_left > 0)
1084            skip_bits(gb, num_bits_left);
1085    }
1086
1087    return get_bits_count(gb) - cnt;
1088}
1089
1090static void sbr_reset(AACContext *ac, SpectralBandReplication *sbr)
1091{
1092    int err;
1093    err = sbr_make_f_master(ac, sbr, &sbr->spectrum_params);
1094    if (err >= 0)
1095        err = sbr_make_f_derived(ac, sbr);
1096    if (err < 0) {
1097        av_log(ac->avctx, AV_LOG_ERROR,
1098               "SBR reset failed. Switching SBR to pure upsampling mode.\n");
1099        sbr_turnoff(sbr);
1100    }
1101}
1102
1103/**
1104 * Decode Spectral Band Replication extension data; reference: table 4.55.
1105 *
1106 * @param   crc flag indicating the presence of CRC checksum
1107 * @param   cnt length of TYPE_FIL syntactic element in bytes
1108 *
1109 * @return  Returns number of bytes consumed from the TYPE_FIL element.
1110 */
1111int AAC_RENAME(ff_decode_sbr_extension)(AACContext *ac, SpectralBandReplication *sbr,
1112                            GetBitContext *gb_host, int crc, int cnt, int id_aac)
1113{
1114    unsigned int num_sbr_bits = 0, num_align_bits;
1115    unsigned bytes_read;
1116    GetBitContext gbc = *gb_host, *gb = &gbc;
1117    skip_bits_long(gb_host, cnt*8 - 4);
1118
1119    sbr->reset = 0;
1120
1121    if (!sbr->sample_rate)
1122        sbr->sample_rate = 2 * ac->oc[1].m4ac.sample_rate; //TODO use the nominal sample rate for arbitrary sample rate support
1123    if (!ac->oc[1].m4ac.ext_sample_rate)
1124        ac->oc[1].m4ac.ext_sample_rate = 2 * ac->oc[1].m4ac.sample_rate;
1125
1126    if (crc) {
1127        skip_bits(gb, 10); // bs_sbr_crc_bits; TODO - implement CRC check
1128        num_sbr_bits += 10;
1129    }
1130
1131    //Save some state from the previous frame.
1132    sbr->kx[0] = sbr->kx[1];
1133    sbr->m[0] = sbr->m[1];
1134    sbr->kx_and_m_pushed = 1;
1135
1136    num_sbr_bits++;
1137    if (get_bits1(gb)) // bs_header_flag
1138        num_sbr_bits += read_sbr_header(sbr, gb);
1139
1140    if (sbr->reset)
1141        sbr_reset(ac, sbr);
1142
1143    if (sbr->start)
1144        num_sbr_bits  += read_sbr_data(ac, sbr, gb, id_aac);
1145
1146    num_align_bits = ((cnt << 3) - 4 - num_sbr_bits) & 7;
1147    bytes_read = ((num_sbr_bits + num_align_bits + 4) >> 3);
1148
1149    if (bytes_read > cnt) {
1150        av_log(ac->avctx, AV_LOG_ERROR,
1151               "Expected to read %d SBR bytes actually read %d.\n", cnt, bytes_read);
1152        sbr_turnoff(sbr);
1153    }
1154    return cnt;
1155}
1156
1157/**
1158 * Analysis QMF Bank (14496-3 sp04 p206)
1159 *
1160 * @param   x       pointer to the beginning of the first sample window
1161 * @param   W       array of complex-valued samples split into subbands
1162 */
1163#ifndef sbr_qmf_analysis
1164#if USE_FIXED
1165static void sbr_qmf_analysis(AVFixedDSPContext *dsp, FFTContext *mdct,
1166#else
1167static void sbr_qmf_analysis(AVFloatDSPContext *dsp, FFTContext *mdct,
1168#endif /* USE_FIXED */
1169                             SBRDSPContext *sbrdsp, const INTFLOAT *in, INTFLOAT *x,
1170                             INTFLOAT z[320], INTFLOAT W[2][32][32][2], int buf_idx)
1171{
1172    int i;
1173#if USE_FIXED
1174    int j;
1175#endif
1176    memcpy(x    , x+1024, (320-32)*sizeof(x[0]));
1177    memcpy(x+288, in,         1024*sizeof(x[0]));
1178    for (i = 0; i < 32; i++) { // numTimeSlots*RATE = 16*2 as 960 sample frames
1179                               // are not supported
1180        dsp->vector_fmul_reverse(z, sbr_qmf_window_ds, x, 320);
1181        sbrdsp->sum64x5(z);
1182        sbrdsp->qmf_pre_shuffle(z);
1183#if USE_FIXED
1184        for (j = 64; j < 128; j++) {
1185            if (z[j] > 1<<24) {
1186                av_log(NULL, AV_LOG_WARNING,
1187                       "sbr_qmf_analysis: value %09d too large, setting to %09d\n",
1188                       z[j], 1<<24);
1189                z[j] = 1<<24;
1190            } else if (z[j] < -(1<<24)) {
1191                av_log(NULL, AV_LOG_WARNING,
1192                       "sbr_qmf_analysis: value %09d too small, setting to %09d\n",
1193                       z[j], -(1<<24));
1194                z[j] = -(1<<24);
1195            }
1196        }
1197#endif
1198        mdct->imdct_half(mdct, z, z+64);
1199        sbrdsp->qmf_post_shuffle(W[buf_idx][i], z);
1200        x += 32;
1201    }
1202}
1203#endif
1204
1205/**
1206 * Synthesis QMF Bank (14496-3 sp04 p206) and Downsampled Synthesis QMF Bank
1207 * (14496-3 sp04 p206)
1208 */
1209#ifndef sbr_qmf_synthesis
1210static void sbr_qmf_synthesis(FFTContext *mdct,
1211#if USE_FIXED
1212                              SBRDSPContext *sbrdsp, AVFixedDSPContext *dsp,
1213#else
1214                              SBRDSPContext *sbrdsp, AVFloatDSPContext *dsp,
1215#endif /* USE_FIXED */
1216                              INTFLOAT *out, INTFLOAT X[2][38][64],
1217                              INTFLOAT mdct_buf[2][64],
1218                              INTFLOAT *v0, int *v_off, const unsigned int div)
1219{
1220    int i, n;
1221    const INTFLOAT *sbr_qmf_window = div ? sbr_qmf_window_ds : sbr_qmf_window_us;
1222    const int step = 128 >> div;
1223    INTFLOAT *v;
1224    for (i = 0; i < 32; i++) {
1225        if (*v_off < step) {
1226            int saved_samples = (1280 - 128) >> div;
1227            memcpy(&v0[SBR_SYNTHESIS_BUF_SIZE - saved_samples], v0, saved_samples * sizeof(INTFLOAT));
1228            *v_off = SBR_SYNTHESIS_BUF_SIZE - saved_samples - step;
1229        } else {
1230            *v_off -= step;
1231        }
1232        v = v0 + *v_off;
1233        if (div) {
1234            for (n = 0; n < 32; n++) {
1235                X[0][i][   n] = -X[0][i][n];
1236                X[0][i][32+n] =  X[1][i][31-n];
1237            }
1238            mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
1239            sbrdsp->qmf_deint_neg(v, mdct_buf[0]);
1240        } else {
1241            sbrdsp->neg_odd_64(X[1][i]);
1242            mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
1243            mdct->imdct_half(mdct, mdct_buf[1], X[1][i]);
1244            sbrdsp->qmf_deint_bfly(v, mdct_buf[1], mdct_buf[0]);
1245        }
1246        dsp->vector_fmul    (out, v                , sbr_qmf_window                       , 64 >> div);
1247        dsp->vector_fmul_add(out, v + ( 192 >> div), sbr_qmf_window + ( 64 >> div), out   , 64 >> div);
1248        dsp->vector_fmul_add(out, v + ( 256 >> div), sbr_qmf_window + (128 >> div), out   , 64 >> div);
1249        dsp->vector_fmul_add(out, v + ( 448 >> div), sbr_qmf_window + (192 >> div), out   , 64 >> div);
1250        dsp->vector_fmul_add(out, v + ( 512 >> div), sbr_qmf_window + (256 >> div), out   , 64 >> div);
1251        dsp->vector_fmul_add(out, v + ( 704 >> div), sbr_qmf_window + (320 >> div), out   , 64 >> div);
1252        dsp->vector_fmul_add(out, v + ( 768 >> div), sbr_qmf_window + (384 >> div), out   , 64 >> div);
1253        dsp->vector_fmul_add(out, v + ( 960 >> div), sbr_qmf_window + (448 >> div), out   , 64 >> div);
1254        dsp->vector_fmul_add(out, v + (1024 >> div), sbr_qmf_window + (512 >> div), out   , 64 >> div);
1255        dsp->vector_fmul_add(out, v + (1216 >> div), sbr_qmf_window + (576 >> div), out   , 64 >> div);
1256        out += 64 >> div;
1257    }
1258}
1259#endif
1260
1261/// Generate the subband filtered lowband
1262static int sbr_lf_gen(AACContext *ac, SpectralBandReplication *sbr,
1263                      INTFLOAT X_low[32][40][2], const INTFLOAT W[2][32][32][2],
1264                      int buf_idx)
1265{
1266    int i, k;
1267    const int t_HFGen = 8;
1268    const int i_f = 32;
1269    memset(X_low, 0, 32*sizeof(*X_low));
1270    for (k = 0; k < sbr->kx[1]; k++) {
1271        for (i = t_HFGen; i < i_f + t_HFGen; i++) {
1272            X_low[k][i][0] = W[buf_idx][i - t_HFGen][k][0];
1273            X_low[k][i][1] = W[buf_idx][i - t_HFGen][k][1];
1274        }
1275    }
1276    buf_idx = 1-buf_idx;
1277    for (k = 0; k < sbr->kx[0]; k++) {
1278        for (i = 0; i < t_HFGen; i++) {
1279            X_low[k][i][0] = W[buf_idx][i + i_f - t_HFGen][k][0];
1280            X_low[k][i][1] = W[buf_idx][i + i_f - t_HFGen][k][1];
1281        }
1282    }
1283    return 0;
1284}
1285
1286/// High Frequency Generator (14496-3 sp04 p215)
1287static int sbr_hf_gen(AACContext *ac, SpectralBandReplication *sbr,
1288                      INTFLOAT X_high[64][40][2], const INTFLOAT X_low[32][40][2],
1289                      const INTFLOAT (*alpha0)[2], const INTFLOAT (*alpha1)[2],
1290                      const INTFLOAT bw_array[5], const uint8_t *t_env,
1291                      int bs_num_env)
1292{
1293    int j, x;
1294    int g = 0;
1295    int k = sbr->kx[1];
1296    for (j = 0; j < sbr->num_patches; j++) {
1297        for (x = 0; x < sbr->patch_num_subbands[j]; x++, k++) {
1298            const int p = sbr->patch_start_subband[j] + x;
1299            while (g <= sbr->n_q && k >= sbr->f_tablenoise[g])
1300                g++;
1301            g--;
1302
1303            if (g < 0) {
1304                av_log(ac->avctx, AV_LOG_ERROR,
1305                       "ERROR : no subband found for frequency %d\n", k);
1306                return -1;
1307            }
1308
1309            sbr->dsp.hf_gen(X_high[k] + ENVELOPE_ADJUSTMENT_OFFSET,
1310                            X_low[p]  + ENVELOPE_ADJUSTMENT_OFFSET,
1311                            alpha0[p], alpha1[p], bw_array[g],
1312                            2 * t_env[0], 2 * t_env[bs_num_env]);
1313        }
1314    }
1315    if (k < sbr->m[1] + sbr->kx[1])
1316        memset(X_high + k, 0, (sbr->m[1] + sbr->kx[1] - k) * sizeof(*X_high));
1317
1318    return 0;
1319}
1320
1321/// Generate the subband filtered lowband
1322static int sbr_x_gen(SpectralBandReplication *sbr, INTFLOAT X[2][38][64],
1323                     const INTFLOAT Y0[38][64][2], const INTFLOAT Y1[38][64][2],
1324                     const INTFLOAT X_low[32][40][2], int ch)
1325{
1326    int k, i;
1327    const int i_f = 32;
1328    const int i_Temp = FFMAX(2*sbr->data[ch].t_env_num_env_old - i_f, 0);
1329    memset(X, 0, 2*sizeof(*X));
1330    for (k = 0; k < sbr->kx[0]; k++) {
1331        for (i = 0; i < i_Temp; i++) {
1332            X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
1333            X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
1334        }
1335    }
1336    for (; k < sbr->kx[0] + sbr->m[0]; k++) {
1337        for (i = 0; i < i_Temp; i++) {
1338            X[0][i][k] = Y0[i + i_f][k][0];
1339            X[1][i][k] = Y0[i + i_f][k][1];
1340        }
1341    }
1342
1343    for (k = 0; k < sbr->kx[1]; k++) {
1344        for (i = i_Temp; i < 38; i++) {
1345            X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
1346            X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
1347        }
1348    }
1349    for (; k < sbr->kx[1] + sbr->m[1]; k++) {
1350        for (i = i_Temp; i < i_f; i++) {
1351            X[0][i][k] = Y1[i][k][0];
1352            X[1][i][k] = Y1[i][k][1];
1353        }
1354    }
1355    return 0;
1356}
1357
1358/** High Frequency Adjustment (14496-3 sp04 p217) and Mapping
1359 * (14496-3 sp04 p217)
1360 */
1361static int sbr_mapping(AACContext *ac, SpectralBandReplication *sbr,
1362                        SBRData *ch_data, int e_a[2])
1363{
1364    int e, i, m;
1365
1366    memset(ch_data->s_indexmapped[1], 0, 7*sizeof(ch_data->s_indexmapped[1]));
1367    for (e = 0; e < ch_data->bs_num_env; e++) {
1368        const unsigned int ilim = sbr->n[ch_data->bs_freq_res[e + 1]];
1369        uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
1370        int k;
1371
1372        if (sbr->kx[1] != table[0]) {
1373            av_log(ac->avctx, AV_LOG_ERROR, "kx != f_table{high,low}[0]. "
1374                   "Derived frequency tables were not regenerated.\n");
1375            sbr_turnoff(sbr);
1376            return AVERROR_BUG;
1377        }
1378        for (i = 0; i < ilim; i++)
1379            for (m = table[i]; m < table[i + 1]; m++)
1380                sbr->e_origmapped[e][m - sbr->kx[1]] = ch_data->env_facs[e+1][i];
1381
1382        // ch_data->bs_num_noise > 1 => 2 noise floors
1383        k = (ch_data->bs_num_noise > 1) && (ch_data->t_env[e] >= ch_data->t_q[1]);
1384        for (i = 0; i < sbr->n_q; i++)
1385            for (m = sbr->f_tablenoise[i]; m < sbr->f_tablenoise[i + 1]; m++)
1386                sbr->q_mapped[e][m - sbr->kx[1]] = ch_data->noise_facs[k+1][i];
1387
1388        for (i = 0; i < sbr->n[1]; i++) {
1389            if (ch_data->bs_add_harmonic_flag) {
1390                const unsigned int m_midpoint =
1391                    (sbr->f_tablehigh[i] + sbr->f_tablehigh[i + 1]) >> 1;
1392
1393                ch_data->s_indexmapped[e + 1][m_midpoint - sbr->kx[1]] = ch_data->bs_add_harmonic[i] *
1394                    (e >= e_a[1] || (ch_data->s_indexmapped[0][m_midpoint - sbr->kx[1]] == 1));
1395            }
1396        }
1397
1398        for (i = 0; i < ilim; i++) {
1399            int additional_sinusoid_present = 0;
1400            for (m = table[i]; m < table[i + 1]; m++) {
1401                if (ch_data->s_indexmapped[e + 1][m - sbr->kx[1]]) {
1402                    additional_sinusoid_present = 1;
1403                    break;
1404                }
1405            }
1406            memset(&sbr->s_mapped[e][table[i] - sbr->kx[1]], additional_sinusoid_present,
1407                   (table[i + 1] - table[i]) * sizeof(sbr->s_mapped[e][0]));
1408        }
1409    }
1410
1411    memcpy(ch_data->s_indexmapped[0], ch_data->s_indexmapped[ch_data->bs_num_env], sizeof(ch_data->s_indexmapped[0]));
1412    return 0;
1413}
1414
1415/// Estimation of current envelope (14496-3 sp04 p218)
1416static void sbr_env_estimate(AAC_FLOAT (*e_curr)[48], INTFLOAT X_high[64][40][2],
1417                             SpectralBandReplication *sbr, SBRData *ch_data)
1418{
1419    int e, m;
1420    int kx1 = sbr->kx[1];
1421
1422    if (sbr->bs_interpol_freq) {
1423        for (e = 0; e < ch_data->bs_num_env; e++) {
1424#if USE_FIXED
1425            const SoftFloat recip_env_size = av_int2sf(0x20000000 / (ch_data->t_env[e + 1] - ch_data->t_env[e]), 30);
1426#else
1427            const float recip_env_size = 0.5f / (ch_data->t_env[e + 1] - ch_data->t_env[e]);
1428#endif /* USE_FIXED */
1429            int ilb = ch_data->t_env[e]     * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1430            int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1431
1432            for (m = 0; m < sbr->m[1]; m++) {
1433                AAC_FLOAT sum = sbr->dsp.sum_square(X_high[m+kx1] + ilb, iub - ilb);
1434#if USE_FIXED
1435                e_curr[e][m] = av_mul_sf(sum, recip_env_size);
1436#else
1437                e_curr[e][m] = sum * recip_env_size;
1438#endif /* USE_FIXED */
1439            }
1440        }
1441    } else {
1442        int k, p;
1443
1444        for (e = 0; e < ch_data->bs_num_env; e++) {
1445            const int env_size = 2 * (ch_data->t_env[e + 1] - ch_data->t_env[e]);
1446            int ilb = ch_data->t_env[e]     * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1447            int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1448            const uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
1449
1450            for (p = 0; p < sbr->n[ch_data->bs_freq_res[e + 1]]; p++) {
1451#if USE_FIXED
1452                SoftFloat sum = FLOAT_0;
1453                const SoftFloat den = av_int2sf(0x20000000 / (env_size * (table[p + 1] - table[p])), 29);
1454                for (k = table[p]; k < table[p + 1]; k++) {
1455                    sum = av_add_sf(sum, sbr->dsp.sum_square(X_high[k] + ilb, iub - ilb));
1456                }
1457                sum = av_mul_sf(sum, den);
1458#else
1459                float sum = 0.0f;
1460                const int den = env_size * (table[p + 1] - table[p]);
1461
1462                for (k = table[p]; k < table[p + 1]; k++) {
1463                    sum += sbr->dsp.sum_square(X_high[k] + ilb, iub - ilb);
1464                }
1465                sum /= den;
1466#endif /* USE_FIXED */
1467                for (k = table[p]; k < table[p + 1]; k++) {
1468                    e_curr[e][k - kx1] = sum;
1469                }
1470            }
1471        }
1472    }
1473}
1474
1475void AAC_RENAME(ff_sbr_apply)(AACContext *ac, SpectralBandReplication *sbr, int id_aac,
1476                  INTFLOAT* L, INTFLOAT* R)
1477{
1478    int downsampled = ac->oc[1].m4ac.ext_sample_rate < sbr->sample_rate;
1479    int ch;
1480    int nch = (id_aac == TYPE_CPE) ? 2 : 1;
1481    int err;
1482
1483    if (id_aac != sbr->id_aac) {
1484        av_log(ac->avctx, id_aac == TYPE_LFE ? AV_LOG_VERBOSE : AV_LOG_WARNING,
1485            "element type mismatch %d != %d\n", id_aac, sbr->id_aac);
1486        sbr_turnoff(sbr);
1487    }
1488
1489    if (sbr->start && !sbr->ready_for_dequant) {
1490        av_log(ac->avctx, AV_LOG_ERROR,
1491               "No quantized data read for sbr_dequant.\n");
1492        sbr_turnoff(sbr);
1493    }
1494
1495    if (!sbr->kx_and_m_pushed) {
1496        sbr->kx[0] = sbr->kx[1];
1497        sbr->m[0] = sbr->m[1];
1498    } else {
1499        sbr->kx_and_m_pushed = 0;
1500    }
1501
1502    if (sbr->start) {
1503        sbr_dequant(sbr, id_aac);
1504        sbr->ready_for_dequant = 0;
1505    }
1506    for (ch = 0; ch < nch; ch++) {
1507        /* decode channel */
1508        sbr_qmf_analysis(ac->fdsp, &sbr->mdct_ana, &sbr->dsp, ch ? R : L, sbr->data[ch].analysis_filterbank_samples,
1509                         (INTFLOAT*)sbr->qmf_filter_scratch,
1510                         sbr->data[ch].W, sbr->data[ch].Ypos);
1511        sbr->c.sbr_lf_gen(ac, sbr, sbr->X_low,
1512                          (const INTFLOAT (*)[32][32][2]) sbr->data[ch].W,
1513                          sbr->data[ch].Ypos);
1514        sbr->data[ch].Ypos ^= 1;
1515        if (sbr->start) {
1516            sbr->c.sbr_hf_inverse_filter(&sbr->dsp, sbr->alpha0, sbr->alpha1,
1517                                         (const INTFLOAT (*)[40][2]) sbr->X_low, sbr->k[0]);
1518            sbr_chirp(sbr, &sbr->data[ch]);
1519            av_assert0(sbr->data[ch].bs_num_env > 0);
1520            sbr_hf_gen(ac, sbr, sbr->X_high,
1521                       (const INTFLOAT (*)[40][2]) sbr->X_low,
1522                       (const INTFLOAT (*)[2]) sbr->alpha0,
1523                       (const INTFLOAT (*)[2]) sbr->alpha1,
1524                       sbr->data[ch].bw_array, sbr->data[ch].t_env,
1525                       sbr->data[ch].bs_num_env);
1526
1527            // hf_adj
1528            err = sbr_mapping(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
1529            if (!err) {
1530                sbr_env_estimate(sbr->e_curr, sbr->X_high, sbr, &sbr->data[ch]);
1531                sbr_gain_calc(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
1532                sbr->c.sbr_hf_assemble(sbr->data[ch].Y[sbr->data[ch].Ypos],
1533                                (const INTFLOAT (*)[40][2]) sbr->X_high,
1534                                sbr, &sbr->data[ch],
1535                                sbr->data[ch].e_a);
1536            }
1537        }
1538
1539        /* synthesis */
1540        sbr->c.sbr_x_gen(sbr, sbr->X[ch],
1541                  (const INTFLOAT (*)[64][2]) sbr->data[ch].Y[1-sbr->data[ch].Ypos],
1542                  (const INTFLOAT (*)[64][2]) sbr->data[ch].Y[  sbr->data[ch].Ypos],
1543                  (const INTFLOAT (*)[40][2]) sbr->X_low, ch);
1544    }
1545
1546    if (ac->oc[1].m4ac.ps == 1) {
1547        if (sbr->ps.common.start) {
1548            AAC_RENAME(ff_ps_apply)(ac->avctx, &sbr->ps, sbr->X[0], sbr->X[1], sbr->kx[1] + sbr->m[1]);
1549        } else {
1550            memcpy(sbr->X[1], sbr->X[0], sizeof(sbr->X[0]));
1551        }
1552        nch = 2;
1553    }
1554
1555    sbr_qmf_synthesis(&sbr->mdct, &sbr->dsp, ac->fdsp,
1556                      L, sbr->X[0], sbr->qmf_filter_scratch,
1557                      sbr->data[0].synthesis_filterbank_samples,
1558                      &sbr->data[0].synthesis_filterbank_samples_offset,
1559                      downsampled);
1560    if (nch == 2)
1561        sbr_qmf_synthesis(&sbr->mdct, &sbr->dsp, ac->fdsp,
1562                          R, sbr->X[1], sbr->qmf_filter_scratch,
1563                          sbr->data[1].synthesis_filterbank_samples,
1564                          &sbr->data[1].synthesis_filterbank_samples_offset,
1565                          downsampled);
1566}
1567
1568static void aacsbr_func_ptr_init(AACSBRContext *c)
1569{
1570    c->sbr_lf_gen            = sbr_lf_gen;
1571    c->sbr_hf_assemble       = sbr_hf_assemble;
1572    c->sbr_x_gen             = sbr_x_gen;
1573    c->sbr_hf_inverse_filter = sbr_hf_inverse_filter;
1574
1575#if !USE_FIXED
1576#if ARCH_MIPS
1577    ff_aacsbr_func_ptr_init_mips(c);
1578#endif
1579#endif
1580}
1581