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libavcodec/aacsbr.c

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00001 /*
00002  * AAC Spectral Band Replication decoding functions
00003  * Copyright (c) 2008-2009 Robert Swain ( rob opendot cl )
00004  * Copyright (c) 2009-2010 Alex Converse <alex.converse@gmail.com>
00005  *
00006  * This file is part of Libav.
00007  *
00008  * Libav is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * Libav is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with Libav; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00029 #include "aac.h"
00030 #include "sbr.h"
00031 #include "aacsbr.h"
00032 #include "aacsbrdata.h"
00033 #include "fft.h"
00034 #include "aacps.h"
00035 #include "libavutil/libm.h"
00036 
00037 #include <stdint.h>
00038 #include <float.h>
00039 
00040 #define ENVELOPE_ADJUSTMENT_OFFSET 2
00041 #define NOISE_FLOOR_OFFSET 6.0f
00042 
00046 enum {
00047     T_HUFFMAN_ENV_1_5DB,
00048     F_HUFFMAN_ENV_1_5DB,
00049     T_HUFFMAN_ENV_BAL_1_5DB,
00050     F_HUFFMAN_ENV_BAL_1_5DB,
00051     T_HUFFMAN_ENV_3_0DB,
00052     F_HUFFMAN_ENV_3_0DB,
00053     T_HUFFMAN_ENV_BAL_3_0DB,
00054     F_HUFFMAN_ENV_BAL_3_0DB,
00055     T_HUFFMAN_NOISE_3_0DB,
00056     T_HUFFMAN_NOISE_BAL_3_0DB,
00057 };
00058 
00062 enum {
00063     FIXFIX,
00064     FIXVAR,
00065     VARFIX,
00066     VARVAR,
00067 };
00068 
00069 enum {
00070     EXTENSION_ID_PS = 2,
00071 };
00072 
00073 static VLC vlc_sbr[10];
00074 static const int8_t vlc_sbr_lav[10] =
00075     { 60, 60, 24, 24, 31, 31, 12, 12, 31, 12 };
00076 static const DECLARE_ALIGNED(16, float, zero64)[64];
00077 
00078 #define SBR_INIT_VLC_STATIC(num, size) \
00079     INIT_VLC_STATIC(&vlc_sbr[num], 9, sbr_tmp[num].table_size / sbr_tmp[num].elem_size,     \
00080                     sbr_tmp[num].sbr_bits ,                      1,                      1, \
00081                     sbr_tmp[num].sbr_codes, sbr_tmp[num].elem_size, sbr_tmp[num].elem_size, \
00082                     size)
00083 
00084 #define SBR_VLC_ROW(name) \
00085     { name ## _codes, name ## _bits, sizeof(name ## _codes), sizeof(name ## _codes[0]) }
00086 
00087 av_cold void ff_aac_sbr_init(void)
00088 {
00089     int n;
00090     static const struct {
00091         const void *sbr_codes, *sbr_bits;
00092         const unsigned int table_size, elem_size;
00093     } sbr_tmp[] = {
00094         SBR_VLC_ROW(t_huffman_env_1_5dB),
00095         SBR_VLC_ROW(f_huffman_env_1_5dB),
00096         SBR_VLC_ROW(t_huffman_env_bal_1_5dB),
00097         SBR_VLC_ROW(f_huffman_env_bal_1_5dB),
00098         SBR_VLC_ROW(t_huffman_env_3_0dB),
00099         SBR_VLC_ROW(f_huffman_env_3_0dB),
00100         SBR_VLC_ROW(t_huffman_env_bal_3_0dB),
00101         SBR_VLC_ROW(f_huffman_env_bal_3_0dB),
00102         SBR_VLC_ROW(t_huffman_noise_3_0dB),
00103         SBR_VLC_ROW(t_huffman_noise_bal_3_0dB),
00104     };
00105 
00106     // SBR VLC table initialization
00107     SBR_INIT_VLC_STATIC(0, 1098);
00108     SBR_INIT_VLC_STATIC(1, 1092);
00109     SBR_INIT_VLC_STATIC(2, 768);
00110     SBR_INIT_VLC_STATIC(3, 1026);
00111     SBR_INIT_VLC_STATIC(4, 1058);
00112     SBR_INIT_VLC_STATIC(5, 1052);
00113     SBR_INIT_VLC_STATIC(6, 544);
00114     SBR_INIT_VLC_STATIC(7, 544);
00115     SBR_INIT_VLC_STATIC(8, 592);
00116     SBR_INIT_VLC_STATIC(9, 512);
00117 
00118     for (n = 1; n < 320; n++)
00119         sbr_qmf_window_us[320 + n] = sbr_qmf_window_us[320 - n];
00120     sbr_qmf_window_us[384] = -sbr_qmf_window_us[384];
00121     sbr_qmf_window_us[512] = -sbr_qmf_window_us[512];
00122 
00123     for (n = 0; n < 320; n++)
00124         sbr_qmf_window_ds[n] = sbr_qmf_window_us[2*n];
00125 
00126     ff_ps_init();
00127 }
00128 
00129 av_cold void ff_aac_sbr_ctx_init(AACContext *ac, SpectralBandReplication *sbr)
00130 {
00131     float mdct_scale;
00132     sbr->kx[0] = sbr->kx[1] = 32; //Typo in spec, kx' inits to 32
00133     sbr->data[0].e_a[1] = sbr->data[1].e_a[1] = -1;
00134     sbr->data[0].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
00135     sbr->data[1].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
00136     /* SBR requires samples to be scaled to +/-32768.0 to work correctly.
00137      * mdct scale factors are adjusted to scale up from +/-1.0 at analysis
00138      * and scale back down at synthesis. */
00139     mdct_scale = ac->avctx->sample_fmt == AV_SAMPLE_FMT_FLT ? 32768.0f : 1.0f;
00140     ff_mdct_init(&sbr->mdct,     7, 1, 1.0 / (64 * mdct_scale));
00141     ff_mdct_init(&sbr->mdct_ana, 7, 1, -2.0 * mdct_scale);
00142     ff_ps_ctx_init(&sbr->ps);
00143 }
00144 
00145 av_cold void ff_aac_sbr_ctx_close(SpectralBandReplication *sbr)
00146 {
00147     ff_mdct_end(&sbr->mdct);
00148     ff_mdct_end(&sbr->mdct_ana);
00149 }
00150 
00151 static int qsort_comparison_function_int16(const void *a, const void *b)
00152 {
00153     return *(const int16_t *)a - *(const int16_t *)b;
00154 }
00155 
00156 static inline int in_table_int16(const int16_t *table, int last_el, int16_t needle)
00157 {
00158     int i;
00159     for (i = 0; i <= last_el; i++)
00160         if (table[i] == needle)
00161             return 1;
00162     return 0;
00163 }
00164 
00166 static void sbr_make_f_tablelim(SpectralBandReplication *sbr)
00167 {
00168     int k;
00169     if (sbr->bs_limiter_bands > 0) {
00170         static const float bands_warped[3] = { 1.32715174233856803909f,   //2^(0.49/1.2)
00171                                                1.18509277094158210129f,   //2^(0.49/2)
00172                                                1.11987160404675912501f }; //2^(0.49/3)
00173         const float lim_bands_per_octave_warped = bands_warped[sbr->bs_limiter_bands - 1];
00174         int16_t patch_borders[7];
00175         uint16_t *in = sbr->f_tablelim + 1, *out = sbr->f_tablelim;
00176 
00177         patch_borders[0] = sbr->kx[1];
00178         for (k = 1; k <= sbr->num_patches; k++)
00179             patch_borders[k] = patch_borders[k-1] + sbr->patch_num_subbands[k-1];
00180 
00181         memcpy(sbr->f_tablelim, sbr->f_tablelow,
00182                (sbr->n[0] + 1) * sizeof(sbr->f_tablelow[0]));
00183         if (sbr->num_patches > 1)
00184             memcpy(sbr->f_tablelim + sbr->n[0] + 1, patch_borders + 1,
00185                    (sbr->num_patches - 1) * sizeof(patch_borders[0]));
00186 
00187         qsort(sbr->f_tablelim, sbr->num_patches + sbr->n[0],
00188               sizeof(sbr->f_tablelim[0]),
00189               qsort_comparison_function_int16);
00190 
00191         sbr->n_lim = sbr->n[0] + sbr->num_patches - 1;
00192         while (out < sbr->f_tablelim + sbr->n_lim) {
00193             if (*in >= *out * lim_bands_per_octave_warped) {
00194                 *++out = *in++;
00195             } else if (*in == *out ||
00196                 !in_table_int16(patch_borders, sbr->num_patches, *in)) {
00197                 in++;
00198                 sbr->n_lim--;
00199             } else if (!in_table_int16(patch_borders, sbr->num_patches, *out)) {
00200                 *out = *in++;
00201                 sbr->n_lim--;
00202             } else {
00203                 *++out = *in++;
00204             }
00205         }
00206     } else {
00207         sbr->f_tablelim[0] = sbr->f_tablelow[0];
00208         sbr->f_tablelim[1] = sbr->f_tablelow[sbr->n[0]];
00209         sbr->n_lim = 1;
00210     }
00211 }
00212 
00213 static unsigned int read_sbr_header(SpectralBandReplication *sbr, GetBitContext *gb)
00214 {
00215     unsigned int cnt = get_bits_count(gb);
00216     uint8_t bs_header_extra_1;
00217     uint8_t bs_header_extra_2;
00218     int old_bs_limiter_bands = sbr->bs_limiter_bands;
00219     SpectrumParameters old_spectrum_params;
00220 
00221     sbr->start = 1;
00222 
00223     // Save last spectrum parameters variables to compare to new ones
00224     memcpy(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters));
00225 
00226     sbr->bs_amp_res_header              = get_bits1(gb);
00227     sbr->spectrum_params.bs_start_freq  = get_bits(gb, 4);
00228     sbr->spectrum_params.bs_stop_freq   = get_bits(gb, 4);
00229     sbr->spectrum_params.bs_xover_band  = get_bits(gb, 3);
00230                                           skip_bits(gb, 2); // bs_reserved
00231 
00232     bs_header_extra_1 = get_bits1(gb);
00233     bs_header_extra_2 = get_bits1(gb);
00234 
00235     if (bs_header_extra_1) {
00236         sbr->spectrum_params.bs_freq_scale  = get_bits(gb, 2);
00237         sbr->spectrum_params.bs_alter_scale = get_bits1(gb);
00238         sbr->spectrum_params.bs_noise_bands = get_bits(gb, 2);
00239     } else {
00240         sbr->spectrum_params.bs_freq_scale  = 2;
00241         sbr->spectrum_params.bs_alter_scale = 1;
00242         sbr->spectrum_params.bs_noise_bands = 2;
00243     }
00244 
00245     // Check if spectrum parameters changed
00246     if (memcmp(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters)))
00247         sbr->reset = 1;
00248 
00249     if (bs_header_extra_2) {
00250         sbr->bs_limiter_bands  = get_bits(gb, 2);
00251         sbr->bs_limiter_gains  = get_bits(gb, 2);
00252         sbr->bs_interpol_freq  = get_bits1(gb);
00253         sbr->bs_smoothing_mode = get_bits1(gb);
00254     } else {
00255         sbr->bs_limiter_bands  = 2;
00256         sbr->bs_limiter_gains  = 2;
00257         sbr->bs_interpol_freq  = 1;
00258         sbr->bs_smoothing_mode = 1;
00259     }
00260 
00261     if (sbr->bs_limiter_bands != old_bs_limiter_bands && !sbr->reset)
00262         sbr_make_f_tablelim(sbr);
00263 
00264     return get_bits_count(gb) - cnt;
00265 }
00266 
00267 static int array_min_int16(const int16_t *array, int nel)
00268 {
00269     int i, min = array[0];
00270     for (i = 1; i < nel; i++)
00271         min = FFMIN(array[i], min);
00272     return min;
00273 }
00274 
00275 static void make_bands(int16_t* bands, int start, int stop, int num_bands)
00276 {
00277     int k, previous, present;
00278     float base, prod;
00279 
00280     base = powf((float)stop / start, 1.0f / num_bands);
00281     prod = start;
00282     previous = start;
00283 
00284     for (k = 0; k < num_bands-1; k++) {
00285         prod *= base;
00286         present  = lrintf(prod);
00287         bands[k] = present - previous;
00288         previous = present;
00289     }
00290     bands[num_bands-1] = stop - previous;
00291 }
00292 
00293 static int check_n_master(AVCodecContext *avctx, int n_master, int bs_xover_band)
00294 {
00295     // Requirements (14496-3 sp04 p205)
00296     if (n_master <= 0) {
00297         av_log(avctx, AV_LOG_ERROR, "Invalid n_master: %d\n", n_master);
00298         return -1;
00299     }
00300     if (bs_xover_band >= n_master) {
00301         av_log(avctx, AV_LOG_ERROR,
00302                "Invalid bitstream, crossover band index beyond array bounds: %d\n",
00303                bs_xover_band);
00304         return -1;
00305     }
00306     return 0;
00307 }
00308 
00310 static int sbr_make_f_master(AACContext *ac, SpectralBandReplication *sbr,
00311                              SpectrumParameters *spectrum)
00312 {
00313     unsigned int temp, max_qmf_subbands;
00314     unsigned int start_min, stop_min;
00315     int k;
00316     const int8_t *sbr_offset_ptr;
00317     int16_t stop_dk[13];
00318 
00319     if (sbr->sample_rate < 32000) {
00320         temp = 3000;
00321     } else if (sbr->sample_rate < 64000) {
00322         temp = 4000;
00323     } else
00324         temp = 5000;
00325 
00326     start_min = ((temp << 7) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
00327     stop_min  = ((temp << 8) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
00328 
00329     switch (sbr->sample_rate) {
00330     case 16000:
00331         sbr_offset_ptr = sbr_offset[0];
00332         break;
00333     case 22050:
00334         sbr_offset_ptr = sbr_offset[1];
00335         break;
00336     case 24000:
00337         sbr_offset_ptr = sbr_offset[2];
00338         break;
00339     case 32000:
00340         sbr_offset_ptr = sbr_offset[3];
00341         break;
00342     case 44100: case 48000: case 64000:
00343         sbr_offset_ptr = sbr_offset[4];
00344         break;
00345     case 88200: case 96000: case 128000: case 176400: case 192000:
00346         sbr_offset_ptr = sbr_offset[5];
00347         break;
00348     default:
00349         av_log(ac->avctx, AV_LOG_ERROR,
00350                "Unsupported sample rate for SBR: %d\n", sbr->sample_rate);
00351         return -1;
00352     }
00353 
00354     sbr->k[0] = start_min + sbr_offset_ptr[spectrum->bs_start_freq];
00355 
00356     if (spectrum->bs_stop_freq < 14) {
00357         sbr->k[2] = stop_min;
00358         make_bands(stop_dk, stop_min, 64, 13);
00359         qsort(stop_dk, 13, sizeof(stop_dk[0]), qsort_comparison_function_int16);
00360         for (k = 0; k < spectrum->bs_stop_freq; k++)
00361             sbr->k[2] += stop_dk[k];
00362     } else if (spectrum->bs_stop_freq == 14) {
00363         sbr->k[2] = 2*sbr->k[0];
00364     } else if (spectrum->bs_stop_freq == 15) {
00365         sbr->k[2] = 3*sbr->k[0];
00366     } else {
00367         av_log(ac->avctx, AV_LOG_ERROR,
00368                "Invalid bs_stop_freq: %d\n", spectrum->bs_stop_freq);
00369         return -1;
00370     }
00371     sbr->k[2] = FFMIN(64, sbr->k[2]);
00372 
00373     // Requirements (14496-3 sp04 p205)
00374     if (sbr->sample_rate <= 32000) {
00375         max_qmf_subbands = 48;
00376     } else if (sbr->sample_rate == 44100) {
00377         max_qmf_subbands = 35;
00378     } else if (sbr->sample_rate >= 48000)
00379         max_qmf_subbands = 32;
00380 
00381     if (sbr->k[2] - sbr->k[0] > max_qmf_subbands) {
00382         av_log(ac->avctx, AV_LOG_ERROR,
00383                "Invalid bitstream, too many QMF subbands: %d\n", sbr->k[2] - sbr->k[0]);
00384         return -1;
00385     }
00386 
00387     if (!spectrum->bs_freq_scale) {
00388         int dk, k2diff;
00389 
00390         dk = spectrum->bs_alter_scale + 1;
00391         sbr->n_master = ((sbr->k[2] - sbr->k[0] + (dk&2)) >> dk) << 1;
00392         if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
00393             return -1;
00394 
00395         for (k = 1; k <= sbr->n_master; k++)
00396             sbr->f_master[k] = dk;
00397 
00398         k2diff = sbr->k[2] - sbr->k[0] - sbr->n_master * dk;
00399         if (k2diff < 0) {
00400             sbr->f_master[1]--;
00401             sbr->f_master[2]-= (k2diff < -1);
00402         } else if (k2diff) {
00403             sbr->f_master[sbr->n_master]++;
00404         }
00405 
00406         sbr->f_master[0] = sbr->k[0];
00407         for (k = 1; k <= sbr->n_master; k++)
00408             sbr->f_master[k] += sbr->f_master[k - 1];
00409 
00410     } else {
00411         int half_bands = 7 - spectrum->bs_freq_scale;      // bs_freq_scale  = {1,2,3}
00412         int two_regions, num_bands_0;
00413         int vdk0_max, vdk1_min;
00414         int16_t vk0[49];
00415 
00416         if (49 * sbr->k[2] > 110 * sbr->k[0]) {
00417             two_regions = 1;
00418             sbr->k[1] = 2 * sbr->k[0];
00419         } else {
00420             two_regions = 0;
00421             sbr->k[1] = sbr->k[2];
00422         }
00423 
00424         num_bands_0 = lrintf(half_bands * log2f(sbr->k[1] / (float)sbr->k[0])) * 2;
00425 
00426         if (num_bands_0 <= 0) { // Requirements (14496-3 sp04 p205)
00427             av_log(ac->avctx, AV_LOG_ERROR, "Invalid num_bands_0: %d\n", num_bands_0);
00428             return -1;
00429         }
00430 
00431         vk0[0] = 0;
00432 
00433         make_bands(vk0+1, sbr->k[0], sbr->k[1], num_bands_0);
00434 
00435         qsort(vk0 + 1, num_bands_0, sizeof(vk0[1]), qsort_comparison_function_int16);
00436         vdk0_max = vk0[num_bands_0];
00437 
00438         vk0[0] = sbr->k[0];
00439         for (k = 1; k <= num_bands_0; k++) {
00440             if (vk0[k] <= 0) { // Requirements (14496-3 sp04 p205)
00441                 av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk0[%d]: %d\n", k, vk0[k]);
00442                 return -1;
00443             }
00444             vk0[k] += vk0[k-1];
00445         }
00446 
00447         if (two_regions) {
00448             int16_t vk1[49];
00449             float invwarp = spectrum->bs_alter_scale ? 0.76923076923076923077f
00450                                                      : 1.0f; // bs_alter_scale = {0,1}
00451             int num_bands_1 = lrintf(half_bands * invwarp *
00452                                      log2f(sbr->k[2] / (float)sbr->k[1])) * 2;
00453 
00454             make_bands(vk1+1, sbr->k[1], sbr->k[2], num_bands_1);
00455 
00456             vdk1_min = array_min_int16(vk1 + 1, num_bands_1);
00457 
00458             if (vdk1_min < vdk0_max) {
00459                 int change;
00460                 qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
00461                 change = FFMIN(vdk0_max - vk1[1], (vk1[num_bands_1] - vk1[1]) >> 1);
00462                 vk1[1]           += change;
00463                 vk1[num_bands_1] -= change;
00464             }
00465 
00466             qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
00467 
00468             vk1[0] = sbr->k[1];
00469             for (k = 1; k <= num_bands_1; k++) {
00470                 if (vk1[k] <= 0) { // Requirements (14496-3 sp04 p205)
00471                     av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk1[%d]: %d\n", k, vk1[k]);
00472                     return -1;
00473                 }
00474                 vk1[k] += vk1[k-1];
00475             }
00476 
00477             sbr->n_master = num_bands_0 + num_bands_1;
00478             if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
00479                 return -1;
00480             memcpy(&sbr->f_master[0],               vk0,
00481                    (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
00482             memcpy(&sbr->f_master[num_bands_0 + 1], vk1 + 1,
00483                     num_bands_1      * sizeof(sbr->f_master[0]));
00484 
00485         } else {
00486             sbr->n_master = num_bands_0;
00487             if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
00488                 return -1;
00489             memcpy(sbr->f_master, vk0, (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
00490         }
00491     }
00492 
00493     return 0;
00494 }
00495 
00497 static int sbr_hf_calc_npatches(AACContext *ac, SpectralBandReplication *sbr)
00498 {
00499     int i, k, sb = 0;
00500     int msb = sbr->k[0];
00501     int usb = sbr->kx[1];
00502     int goal_sb = ((1000 << 11) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
00503 
00504     sbr->num_patches = 0;
00505 
00506     if (goal_sb < sbr->kx[1] + sbr->m[1]) {
00507         for (k = 0; sbr->f_master[k] < goal_sb; k++) ;
00508     } else
00509         k = sbr->n_master;
00510 
00511     do {
00512         int odd = 0;
00513         for (i = k; i == k || sb > (sbr->k[0] - 1 + msb - odd); i--) {
00514             sb = sbr->f_master[i];
00515             odd = (sb + sbr->k[0]) & 1;
00516         }
00517 
00518         // Requirements (14496-3 sp04 p205) sets the maximum number of patches to 5.
00519         // After this check the final number of patches can still be six which is
00520         // illegal however the Coding Technologies decoder check stream has a final
00521         // count of 6 patches
00522         if (sbr->num_patches > 5) {
00523             av_log(ac->avctx, AV_LOG_ERROR, "Too many patches: %d\n", sbr->num_patches);
00524             return -1;
00525         }
00526 
00527         sbr->patch_num_subbands[sbr->num_patches]  = FFMAX(sb - usb, 0);
00528         sbr->patch_start_subband[sbr->num_patches] = sbr->k[0] - odd - sbr->patch_num_subbands[sbr->num_patches];
00529 
00530         if (sbr->patch_num_subbands[sbr->num_patches] > 0) {
00531             usb = sb;
00532             msb = sb;
00533             sbr->num_patches++;
00534         } else
00535             msb = sbr->kx[1];
00536 
00537         if (sbr->f_master[k] - sb < 3)
00538             k = sbr->n_master;
00539     } while (sb != sbr->kx[1] + sbr->m[1]);
00540 
00541     if (sbr->patch_num_subbands[sbr->num_patches-1] < 3 && sbr->num_patches > 1)
00542         sbr->num_patches--;
00543 
00544     return 0;
00545 }
00546 
00548 static int sbr_make_f_derived(AACContext *ac, SpectralBandReplication *sbr)
00549 {
00550     int k, temp;
00551 
00552     sbr->n[1] = sbr->n_master - sbr->spectrum_params.bs_xover_band;
00553     sbr->n[0] = (sbr->n[1] + 1) >> 1;
00554 
00555     memcpy(sbr->f_tablehigh, &sbr->f_master[sbr->spectrum_params.bs_xover_band],
00556            (sbr->n[1] + 1) * sizeof(sbr->f_master[0]));
00557     sbr->m[1] = sbr->f_tablehigh[sbr->n[1]] - sbr->f_tablehigh[0];
00558     sbr->kx[1] = sbr->f_tablehigh[0];
00559 
00560     // Requirements (14496-3 sp04 p205)
00561     if (sbr->kx[1] + sbr->m[1] > 64) {
00562         av_log(ac->avctx, AV_LOG_ERROR,
00563                "Stop frequency border too high: %d\n", sbr->kx[1] + sbr->m[1]);
00564         return -1;
00565     }
00566     if (sbr->kx[1] > 32) {
00567         av_log(ac->avctx, AV_LOG_ERROR, "Start frequency border too high: %d\n", sbr->kx[1]);
00568         return -1;
00569     }
00570 
00571     sbr->f_tablelow[0] = sbr->f_tablehigh[0];
00572     temp = sbr->n[1] & 1;
00573     for (k = 1; k <= sbr->n[0]; k++)
00574         sbr->f_tablelow[k] = sbr->f_tablehigh[2 * k - temp];
00575 
00576     sbr->n_q = FFMAX(1, lrintf(sbr->spectrum_params.bs_noise_bands *
00577                                log2f(sbr->k[2] / (float)sbr->kx[1]))); // 0 <= bs_noise_bands <= 3
00578     if (sbr->n_q > 5) {
00579         av_log(ac->avctx, AV_LOG_ERROR, "Too many noise floor scale factors: %d\n", sbr->n_q);
00580         return -1;
00581     }
00582 
00583     sbr->f_tablenoise[0] = sbr->f_tablelow[0];
00584     temp = 0;
00585     for (k = 1; k <= sbr->n_q; k++) {
00586         temp += (sbr->n[0] - temp) / (sbr->n_q + 1 - k);
00587         sbr->f_tablenoise[k] = sbr->f_tablelow[temp];
00588     }
00589 
00590     if (sbr_hf_calc_npatches(ac, sbr) < 0)
00591         return -1;
00592 
00593     sbr_make_f_tablelim(sbr);
00594 
00595     sbr->data[0].f_indexnoise = 0;
00596     sbr->data[1].f_indexnoise = 0;
00597 
00598     return 0;
00599 }
00600 
00601 static av_always_inline void get_bits1_vector(GetBitContext *gb, uint8_t *vec,
00602                                               int elements)
00603 {
00604     int i;
00605     for (i = 0; i < elements; i++) {
00606         vec[i] = get_bits1(gb);
00607     }
00608 }
00609 
00611 static const int8_t ceil_log2[] = {
00612     0, 1, 2, 2, 3, 3,
00613 };
00614 
00615 static int read_sbr_grid(AACContext *ac, SpectralBandReplication *sbr,
00616                          GetBitContext *gb, SBRData *ch_data)
00617 {
00618     int i;
00619     unsigned bs_pointer = 0;
00620     // frameLengthFlag ? 15 : 16; 960 sample length frames unsupported; this value is numTimeSlots
00621     int abs_bord_trail = 16;
00622     int num_rel_lead, num_rel_trail;
00623     unsigned bs_num_env_old = ch_data->bs_num_env;
00624 
00625     ch_data->bs_freq_res[0] = ch_data->bs_freq_res[ch_data->bs_num_env];
00626     ch_data->bs_amp_res = sbr->bs_amp_res_header;
00627     ch_data->t_env_num_env_old = ch_data->t_env[bs_num_env_old];
00628 
00629     switch (ch_data->bs_frame_class = get_bits(gb, 2)) {
00630     case FIXFIX:
00631         ch_data->bs_num_env                 = 1 << get_bits(gb, 2);
00632         num_rel_lead                        = ch_data->bs_num_env - 1;
00633         if (ch_data->bs_num_env == 1)
00634             ch_data->bs_amp_res = 0;
00635 
00636         if (ch_data->bs_num_env > 4) {
00637             av_log(ac->avctx, AV_LOG_ERROR,
00638                    "Invalid bitstream, too many SBR envelopes in FIXFIX type SBR frame: %d\n",
00639                    ch_data->bs_num_env);
00640             return -1;
00641         }
00642 
00643         ch_data->t_env[0]                   = 0;
00644         ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
00645 
00646         abs_bord_trail = (abs_bord_trail + (ch_data->bs_num_env >> 1)) /
00647                    ch_data->bs_num_env;
00648         for (i = 0; i < num_rel_lead; i++)
00649             ch_data->t_env[i + 1] = ch_data->t_env[i] + abs_bord_trail;
00650 
00651         ch_data->bs_freq_res[1] = get_bits1(gb);
00652         for (i = 1; i < ch_data->bs_num_env; i++)
00653             ch_data->bs_freq_res[i + 1] = ch_data->bs_freq_res[1];
00654         break;
00655     case FIXVAR:
00656         abs_bord_trail                     += get_bits(gb, 2);
00657         num_rel_trail                       = get_bits(gb, 2);
00658         ch_data->bs_num_env                 = num_rel_trail + 1;
00659         ch_data->t_env[0]                   = 0;
00660         ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
00661 
00662         for (i = 0; i < num_rel_trail; i++)
00663             ch_data->t_env[ch_data->bs_num_env - 1 - i] =
00664                 ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
00665 
00666         bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
00667 
00668         for (i = 0; i < ch_data->bs_num_env; i++)
00669             ch_data->bs_freq_res[ch_data->bs_num_env - i] = get_bits1(gb);
00670         break;
00671     case VARFIX:
00672         ch_data->t_env[0]                   = get_bits(gb, 2);
00673         num_rel_lead                        = get_bits(gb, 2);
00674         ch_data->bs_num_env                 = num_rel_lead + 1;
00675         ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
00676 
00677         for (i = 0; i < num_rel_lead; i++)
00678             ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
00679 
00680         bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
00681 
00682         get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
00683         break;
00684     case VARVAR:
00685         ch_data->t_env[0]                   = get_bits(gb, 2);
00686         abs_bord_trail                     += get_bits(gb, 2);
00687         num_rel_lead                        = get_bits(gb, 2);
00688         num_rel_trail                       = get_bits(gb, 2);
00689         ch_data->bs_num_env                 = num_rel_lead + num_rel_trail + 1;
00690 
00691         if (ch_data->bs_num_env > 5) {
00692             av_log(ac->avctx, AV_LOG_ERROR,
00693                    "Invalid bitstream, too many SBR envelopes in VARVAR type SBR frame: %d\n",
00694                    ch_data->bs_num_env);
00695             return -1;
00696         }
00697 
00698         ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
00699 
00700         for (i = 0; i < num_rel_lead; i++)
00701             ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
00702         for (i = 0; i < num_rel_trail; i++)
00703             ch_data->t_env[ch_data->bs_num_env - 1 - i] =
00704                 ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
00705 
00706         bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
00707 
00708         get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
00709         break;
00710     }
00711 
00712     if (bs_pointer > ch_data->bs_num_env + 1) {
00713         av_log(ac->avctx, AV_LOG_ERROR,
00714                "Invalid bitstream, bs_pointer points to a middle noise border outside the time borders table: %d\n",
00715                bs_pointer);
00716         return -1;
00717     }
00718 
00719     for (i = 1; i <= ch_data->bs_num_env; i++) {
00720         if (ch_data->t_env[i-1] > ch_data->t_env[i]) {
00721             av_log(ac->avctx, AV_LOG_ERROR, "Non monotone time borders\n");
00722             return -1;
00723         }
00724     }
00725 
00726     ch_data->bs_num_noise = (ch_data->bs_num_env > 1) + 1;
00727 
00728     ch_data->t_q[0]                     = ch_data->t_env[0];
00729     ch_data->t_q[ch_data->bs_num_noise] = ch_data->t_env[ch_data->bs_num_env];
00730     if (ch_data->bs_num_noise > 1) {
00731         unsigned int idx;
00732         if (ch_data->bs_frame_class == FIXFIX) {
00733             idx = ch_data->bs_num_env >> 1;
00734         } else if (ch_data->bs_frame_class & 1) { // FIXVAR or VARVAR
00735             idx = ch_data->bs_num_env - FFMAX(bs_pointer - 1, 1);
00736         } else { // VARFIX
00737             if (!bs_pointer)
00738                 idx = 1;
00739             else if (bs_pointer == 1)
00740                 idx = ch_data->bs_num_env - 1;
00741             else // bs_pointer > 1
00742                 idx = bs_pointer - 1;
00743         }
00744         ch_data->t_q[1] = ch_data->t_env[idx];
00745     }
00746 
00747     ch_data->e_a[0] = -(ch_data->e_a[1] != bs_num_env_old); // l_APrev
00748     ch_data->e_a[1] = -1;
00749     if ((ch_data->bs_frame_class & 1) && bs_pointer) { // FIXVAR or VARVAR and bs_pointer != 0
00750         ch_data->e_a[1] = ch_data->bs_num_env + 1 - bs_pointer;
00751     } else if ((ch_data->bs_frame_class == 2) && (bs_pointer > 1)) // VARFIX and bs_pointer > 1
00752         ch_data->e_a[1] = bs_pointer - 1;
00753 
00754     return 0;
00755 }
00756 
00757 static void copy_sbr_grid(SBRData *dst, const SBRData *src) {
00758     //These variables are saved from the previous frame rather than copied
00759     dst->bs_freq_res[0]    = dst->bs_freq_res[dst->bs_num_env];
00760     dst->t_env_num_env_old = dst->t_env[dst->bs_num_env];
00761     dst->e_a[0]            = -(dst->e_a[1] != dst->bs_num_env);
00762 
00763     //These variables are read from the bitstream and therefore copied
00764     memcpy(dst->bs_freq_res+1, src->bs_freq_res+1, sizeof(dst->bs_freq_res)-sizeof(*dst->bs_freq_res));
00765     memcpy(dst->t_env,         src->t_env,         sizeof(dst->t_env));
00766     memcpy(dst->t_q,           src->t_q,           sizeof(dst->t_q));
00767     dst->bs_num_env        = src->bs_num_env;
00768     dst->bs_amp_res        = src->bs_amp_res;
00769     dst->bs_num_noise      = src->bs_num_noise;
00770     dst->bs_frame_class    = src->bs_frame_class;
00771     dst->e_a[1]            = src->e_a[1];
00772 }
00773 
00775 static void read_sbr_dtdf(SpectralBandReplication *sbr, GetBitContext *gb,
00776                           SBRData *ch_data)
00777 {
00778     get_bits1_vector(gb, ch_data->bs_df_env,   ch_data->bs_num_env);
00779     get_bits1_vector(gb, ch_data->bs_df_noise, ch_data->bs_num_noise);
00780 }
00781 
00783 static void read_sbr_invf(SpectralBandReplication *sbr, GetBitContext *gb,
00784                           SBRData *ch_data)
00785 {
00786     int i;
00787 
00788     memcpy(ch_data->bs_invf_mode[1], ch_data->bs_invf_mode[0], 5 * sizeof(uint8_t));
00789     for (i = 0; i < sbr->n_q; i++)
00790         ch_data->bs_invf_mode[0][i] = get_bits(gb, 2);
00791 }
00792 
00793 static void read_sbr_envelope(SpectralBandReplication *sbr, GetBitContext *gb,
00794                               SBRData *ch_data, int ch)
00795 {
00796     int bits;
00797     int i, j, k;
00798     VLC_TYPE (*t_huff)[2], (*f_huff)[2];
00799     int t_lav, f_lav;
00800     const int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
00801     const int odd = sbr->n[1] & 1;
00802 
00803     if (sbr->bs_coupling && ch) {
00804         if (ch_data->bs_amp_res) {
00805             bits   = 5;
00806             t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_3_0DB].table;
00807             t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_3_0DB];
00808             f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
00809             f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
00810         } else {
00811             bits   = 6;
00812             t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_1_5DB].table;
00813             t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_1_5DB];
00814             f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_1_5DB].table;
00815             f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_1_5DB];
00816         }
00817     } else {
00818         if (ch_data->bs_amp_res) {
00819             bits   = 6;
00820             t_huff = vlc_sbr[T_HUFFMAN_ENV_3_0DB].table;
00821             t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_3_0DB];
00822             f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
00823             f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
00824         } else {
00825             bits   = 7;
00826             t_huff = vlc_sbr[T_HUFFMAN_ENV_1_5DB].table;
00827             t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_1_5DB];
00828             f_huff = vlc_sbr[F_HUFFMAN_ENV_1_5DB].table;
00829             f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_1_5DB];
00830         }
00831     }
00832 
00833     for (i = 0; i < ch_data->bs_num_env; i++) {
00834         if (ch_data->bs_df_env[i]) {
00835             // bs_freq_res[0] == bs_freq_res[bs_num_env] from prev frame
00836             if (ch_data->bs_freq_res[i + 1] == ch_data->bs_freq_res[i]) {
00837                 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
00838                     ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
00839             } else if (ch_data->bs_freq_res[i + 1]) {
00840                 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
00841                     k = (j + odd) >> 1; // find k such that f_tablelow[k] <= f_tablehigh[j] < f_tablelow[k + 1]
00842                     ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
00843                 }
00844             } else {
00845                 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
00846                     k = j ? 2*j - odd : 0; // find k such that f_tablehigh[k] == f_tablelow[j]
00847                     ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
00848                 }
00849             }
00850         } else {
00851             ch_data->env_facs[i + 1][0] = delta * get_bits(gb, bits); // bs_env_start_value_balance
00852             for (j = 1; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
00853                 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);
00854         }
00855     }
00856 
00857     //assign 0th elements of env_facs from last elements
00858     memcpy(ch_data->env_facs[0], ch_data->env_facs[ch_data->bs_num_env],
00859            sizeof(ch_data->env_facs[0]));
00860 }
00861 
00862 static void read_sbr_noise(SpectralBandReplication *sbr, GetBitContext *gb,
00863                            SBRData *ch_data, int ch)
00864 {
00865     int i, j;
00866     VLC_TYPE (*t_huff)[2], (*f_huff)[2];
00867     int t_lav, f_lav;
00868     int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
00869 
00870     if (sbr->bs_coupling && ch) {
00871         t_huff = vlc_sbr[T_HUFFMAN_NOISE_BAL_3_0DB].table;
00872         t_lav  = vlc_sbr_lav[T_HUFFMAN_NOISE_BAL_3_0DB];
00873         f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
00874         f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
00875     } else {
00876         t_huff = vlc_sbr[T_HUFFMAN_NOISE_3_0DB].table;
00877         t_lav  = vlc_sbr_lav[T_HUFFMAN_NOISE_3_0DB];
00878         f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
00879         f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
00880     }
00881 
00882     for (i = 0; i < ch_data->bs_num_noise; i++) {
00883         if (ch_data->bs_df_noise[i]) {
00884             for (j = 0; j < sbr->n_q; j++)
00885                 ch_data->noise_facs[i + 1][j] = ch_data->noise_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 2) - t_lav);
00886         } else {
00887             ch_data->noise_facs[i + 1][0] = delta * get_bits(gb, 5); // bs_noise_start_value_balance or bs_noise_start_value_level
00888             for (j = 1; j < sbr->n_q; j++)
00889                 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);
00890         }
00891     }
00892 
00893     //assign 0th elements of noise_facs from last elements
00894     memcpy(ch_data->noise_facs[0], ch_data->noise_facs[ch_data->bs_num_noise],
00895            sizeof(ch_data->noise_facs[0]));
00896 }
00897 
00898 static void read_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
00899                                GetBitContext *gb,
00900                                int bs_extension_id, int *num_bits_left)
00901 {
00902     switch (bs_extension_id) {
00903     case EXTENSION_ID_PS:
00904         if (!ac->m4ac.ps) {
00905             av_log(ac->avctx, AV_LOG_ERROR, "Parametric Stereo signaled to be not-present but was found in the bitstream.\n");
00906             skip_bits_long(gb, *num_bits_left); // bs_fill_bits
00907             *num_bits_left = 0;
00908         } else {
00909 #if 1
00910             *num_bits_left -= ff_ps_read_data(ac->avctx, gb, &sbr->ps, *num_bits_left);
00911 #else
00912             av_log_missing_feature(ac->avctx, "Parametric Stereo is", 0);
00913             skip_bits_long(gb, *num_bits_left); // bs_fill_bits
00914             *num_bits_left = 0;
00915 #endif
00916         }
00917         break;
00918     default:
00919         av_log_missing_feature(ac->avctx, "Reserved SBR extensions are", 1);
00920         skip_bits_long(gb, *num_bits_left); // bs_fill_bits
00921         *num_bits_left = 0;
00922         break;
00923     }
00924 }
00925 
00926 static int read_sbr_single_channel_element(AACContext *ac,
00927                                             SpectralBandReplication *sbr,
00928                                             GetBitContext *gb)
00929 {
00930     if (get_bits1(gb)) // bs_data_extra
00931         skip_bits(gb, 4); // bs_reserved
00932 
00933     if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
00934         return -1;
00935     read_sbr_dtdf(sbr, gb, &sbr->data[0]);
00936     read_sbr_invf(sbr, gb, &sbr->data[0]);
00937     read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
00938     read_sbr_noise(sbr, gb, &sbr->data[0], 0);
00939 
00940     if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
00941         get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
00942 
00943     return 0;
00944 }
00945 
00946 static int read_sbr_channel_pair_element(AACContext *ac,
00947                                           SpectralBandReplication *sbr,
00948                                           GetBitContext *gb)
00949 {
00950     if (get_bits1(gb))    // bs_data_extra
00951         skip_bits(gb, 8); // bs_reserved
00952 
00953     if ((sbr->bs_coupling = get_bits1(gb))) {
00954         if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
00955             return -1;
00956         copy_sbr_grid(&sbr->data[1], &sbr->data[0]);
00957         read_sbr_dtdf(sbr, gb, &sbr->data[0]);
00958         read_sbr_dtdf(sbr, gb, &sbr->data[1]);
00959         read_sbr_invf(sbr, gb, &sbr->data[0]);
00960         memcpy(sbr->data[1].bs_invf_mode[1], sbr->data[1].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
00961         memcpy(sbr->data[1].bs_invf_mode[0], sbr->data[0].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
00962         read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
00963         read_sbr_noise(sbr, gb, &sbr->data[0], 0);
00964         read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
00965         read_sbr_noise(sbr, gb, &sbr->data[1], 1);
00966     } else {
00967         if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]) ||
00968             read_sbr_grid(ac, sbr, gb, &sbr->data[1]))
00969             return -1;
00970         read_sbr_dtdf(sbr, gb, &sbr->data[0]);
00971         read_sbr_dtdf(sbr, gb, &sbr->data[1]);
00972         read_sbr_invf(sbr, gb, &sbr->data[0]);
00973         read_sbr_invf(sbr, gb, &sbr->data[1]);
00974         read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
00975         read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
00976         read_sbr_noise(sbr, gb, &sbr->data[0], 0);
00977         read_sbr_noise(sbr, gb, &sbr->data[1], 1);
00978     }
00979 
00980     if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
00981         get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
00982     if ((sbr->data[1].bs_add_harmonic_flag = get_bits1(gb)))
00983         get_bits1_vector(gb, sbr->data[1].bs_add_harmonic, sbr->n[1]);
00984 
00985     return 0;
00986 }
00987 
00988 static unsigned int read_sbr_data(AACContext *ac, SpectralBandReplication *sbr,
00989                                   GetBitContext *gb, int id_aac)
00990 {
00991     unsigned int cnt = get_bits_count(gb);
00992 
00993     if (id_aac == TYPE_SCE || id_aac == TYPE_CCE) {
00994         if (read_sbr_single_channel_element(ac, sbr, gb)) {
00995             sbr->start = 0;
00996             return get_bits_count(gb) - cnt;
00997         }
00998     } else if (id_aac == TYPE_CPE) {
00999         if (read_sbr_channel_pair_element(ac, sbr, gb)) {
01000             sbr->start = 0;
01001             return get_bits_count(gb) - cnt;
01002         }
01003     } else {
01004         av_log(ac->avctx, AV_LOG_ERROR,
01005             "Invalid bitstream - cannot apply SBR to element type %d\n", id_aac);
01006         sbr->start = 0;
01007         return get_bits_count(gb) - cnt;
01008     }
01009     if (get_bits1(gb)) { // bs_extended_data
01010         int num_bits_left = get_bits(gb, 4); // bs_extension_size
01011         if (num_bits_left == 15)
01012             num_bits_left += get_bits(gb, 8); // bs_esc_count
01013 
01014         num_bits_left <<= 3;
01015         while (num_bits_left > 7) {
01016             num_bits_left -= 2;
01017             read_sbr_extension(ac, sbr, gb, get_bits(gb, 2), &num_bits_left); // bs_extension_id
01018         }
01019         if (num_bits_left < 0) {
01020             av_log(ac->avctx, AV_LOG_ERROR, "SBR Extension over read.\n");
01021         }
01022         if (num_bits_left > 0)
01023             skip_bits(gb, num_bits_left);
01024     }
01025 
01026     return get_bits_count(gb) - cnt;
01027 }
01028 
01029 static void sbr_reset(AACContext *ac, SpectralBandReplication *sbr)
01030 {
01031     int err;
01032     err = sbr_make_f_master(ac, sbr, &sbr->spectrum_params);
01033     if (err >= 0)
01034         err = sbr_make_f_derived(ac, sbr);
01035     if (err < 0) {
01036         av_log(ac->avctx, AV_LOG_ERROR,
01037                "SBR reset failed. Switching SBR to pure upsampling mode.\n");
01038         sbr->start = 0;
01039     }
01040 }
01041 
01050 int ff_decode_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
01051                             GetBitContext *gb_host, int crc, int cnt, int id_aac)
01052 {
01053     unsigned int num_sbr_bits = 0, num_align_bits;
01054     unsigned bytes_read;
01055     GetBitContext gbc = *gb_host, *gb = &gbc;
01056     skip_bits_long(gb_host, cnt*8 - 4);
01057 
01058     sbr->reset = 0;
01059 
01060     if (!sbr->sample_rate)
01061         sbr->sample_rate = 2 * ac->m4ac.sample_rate; //TODO use the nominal sample rate for arbitrary sample rate support
01062     if (!ac->m4ac.ext_sample_rate)
01063         ac->m4ac.ext_sample_rate = 2 * ac->m4ac.sample_rate;
01064 
01065     if (crc) {
01066         skip_bits(gb, 10); // bs_sbr_crc_bits; TODO - implement CRC check
01067         num_sbr_bits += 10;
01068     }
01069 
01070     //Save some state from the previous frame.
01071     sbr->kx[0] = sbr->kx[1];
01072     sbr->m[0] = sbr->m[1];
01073 
01074     num_sbr_bits++;
01075     if (get_bits1(gb)) // bs_header_flag
01076         num_sbr_bits += read_sbr_header(sbr, gb);
01077 
01078     if (sbr->reset)
01079         sbr_reset(ac, sbr);
01080 
01081     if (sbr->start)
01082         num_sbr_bits  += read_sbr_data(ac, sbr, gb, id_aac);
01083 
01084     num_align_bits = ((cnt << 3) - 4 - num_sbr_bits) & 7;
01085     bytes_read = ((num_sbr_bits + num_align_bits + 4) >> 3);
01086 
01087     if (bytes_read > cnt) {
01088         av_log(ac->avctx, AV_LOG_ERROR,
01089                "Expected to read %d SBR bytes actually read %d.\n", cnt, bytes_read);
01090     }
01091     return cnt;
01092 }
01093 
01095 static void sbr_dequant(SpectralBandReplication *sbr, int id_aac)
01096 {
01097     int k, e;
01098     int ch;
01099 
01100     if (id_aac == TYPE_CPE && sbr->bs_coupling) {
01101         float alpha      = sbr->data[0].bs_amp_res ?  1.0f :  0.5f;
01102         float pan_offset = sbr->data[0].bs_amp_res ? 12.0f : 24.0f;
01103         for (e = 1; e <= sbr->data[0].bs_num_env; e++) {
01104             for (k = 0; k < sbr->n[sbr->data[0].bs_freq_res[e]]; k++) {
01105                 float temp1 = exp2f(sbr->data[0].env_facs[e][k] * alpha + 7.0f);
01106                 float temp2 = exp2f((pan_offset - sbr->data[1].env_facs[e][k]) * alpha);
01107                 float fac   = temp1 / (1.0f + temp2);
01108                 sbr->data[0].env_facs[e][k] = fac;
01109                 sbr->data[1].env_facs[e][k] = fac * temp2;
01110             }
01111         }
01112         for (e = 1; e <= sbr->data[0].bs_num_noise; e++) {
01113             for (k = 0; k < sbr->n_q; k++) {
01114                 float temp1 = exp2f(NOISE_FLOOR_OFFSET - sbr->data[0].noise_facs[e][k] + 1);
01115                 float temp2 = exp2f(12 - sbr->data[1].noise_facs[e][k]);
01116                 float fac   = temp1 / (1.0f + temp2);
01117                 sbr->data[0].noise_facs[e][k] = fac;
01118                 sbr->data[1].noise_facs[e][k] = fac * temp2;
01119             }
01120         }
01121     } else { // SCE or one non-coupled CPE
01122         for (ch = 0; ch < (id_aac == TYPE_CPE) + 1; ch++) {
01123             float alpha = sbr->data[ch].bs_amp_res ? 1.0f : 0.5f;
01124             for (e = 1; e <= sbr->data[ch].bs_num_env; e++)
01125                 for (k = 0; k < sbr->n[sbr->data[ch].bs_freq_res[e]]; k++)
01126                     sbr->data[ch].env_facs[e][k] =
01127                         exp2f(alpha * sbr->data[ch].env_facs[e][k] + 6.0f);
01128             for (e = 1; e <= sbr->data[ch].bs_num_noise; e++)
01129                 for (k = 0; k < sbr->n_q; k++)
01130                     sbr->data[ch].noise_facs[e][k] =
01131                         exp2f(NOISE_FLOOR_OFFSET - sbr->data[ch].noise_facs[e][k]);
01132         }
01133     }
01134 }
01135 
01142 static void sbr_qmf_analysis(DSPContext *dsp, FFTContext *mdct, const float *in, float *x,
01143                              float z[320], float W[2][32][32][2])
01144 {
01145     int i, k;
01146     memcpy(W[0], W[1], sizeof(W[0]));
01147     memcpy(x    , x+1024, (320-32)*sizeof(x[0]));
01148     memcpy(x+288, in,         1024*sizeof(x[0]));
01149     for (i = 0; i < 32; i++) { // numTimeSlots*RATE = 16*2 as 960 sample frames
01150                                // are not supported
01151         dsp->vector_fmul_reverse(z, sbr_qmf_window_ds, x, 320);
01152         for (k = 0; k < 64; k++) {
01153             float f = z[k] + z[k + 64] + z[k + 128] + z[k + 192] + z[k + 256];
01154             z[k] = f;
01155         }
01156         //Shuffle to IMDCT
01157         z[64] = z[0];
01158         for (k = 1; k < 32; k++) {
01159             z[64+2*k-1] =  z[   k];
01160             z[64+2*k  ] = -z[64-k];
01161         }
01162         z[64+63] = z[32];
01163 
01164         mdct->imdct_half(mdct, z, z+64);
01165         for (k = 0; k < 32; k++) {
01166             W[1][i][k][0] = -z[63-k];
01167             W[1][i][k][1] = z[k];
01168         }
01169         x += 32;
01170     }
01171 }
01172 
01177 static void sbr_qmf_synthesis(DSPContext *dsp, FFTContext *mdct,
01178                               float *out, float X[2][38][64],
01179                               float mdct_buf[2][64],
01180                               float *v0, int *v_off, const unsigned int div)
01181 {
01182     int i, n;
01183     const float *sbr_qmf_window = div ? sbr_qmf_window_ds : sbr_qmf_window_us;
01184     const int step = 128 >> div;
01185     float *v;
01186     for (i = 0; i < 32; i++) {
01187         if (*v_off < step) {
01188             int saved_samples = (1280 - 128) >> div;
01189             memcpy(&v0[SBR_SYNTHESIS_BUF_SIZE - saved_samples], v0, saved_samples * sizeof(float));
01190             *v_off = SBR_SYNTHESIS_BUF_SIZE - saved_samples - step;
01191         } else {
01192             *v_off -= step;
01193         }
01194         v = v0 + *v_off;
01195         if (div) {
01196             for (n = 0; n < 32; n++) {
01197                 X[0][i][   n] = -X[0][i][n];
01198                 X[0][i][32+n] =  X[1][i][31-n];
01199             }
01200             mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
01201             for (n = 0; n < 32; n++) {
01202                 v[     n] =  mdct_buf[0][63 - 2*n];
01203                 v[63 - n] = -mdct_buf[0][62 - 2*n];
01204             }
01205         } else {
01206             for (n = 1; n < 64; n+=2) {
01207                 X[1][i][n] = -X[1][i][n];
01208             }
01209             mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
01210             mdct->imdct_half(mdct, mdct_buf[1], X[1][i]);
01211             for (n = 0; n < 64; n++) {
01212                 v[      n] = -mdct_buf[0][63 -   n] + mdct_buf[1][  n    ];
01213                 v[127 - n] =  mdct_buf[0][63 -   n] + mdct_buf[1][  n    ];
01214             }
01215         }
01216         dsp->vector_fmul_add(out, v                , sbr_qmf_window               , zero64, 64 >> div);
01217         dsp->vector_fmul_add(out, v + ( 192 >> div), sbr_qmf_window + ( 64 >> div), out   , 64 >> div);
01218         dsp->vector_fmul_add(out, v + ( 256 >> div), sbr_qmf_window + (128 >> div), out   , 64 >> div);
01219         dsp->vector_fmul_add(out, v + ( 448 >> div), sbr_qmf_window + (192 >> div), out   , 64 >> div);
01220         dsp->vector_fmul_add(out, v + ( 512 >> div), sbr_qmf_window + (256 >> div), out   , 64 >> div);
01221         dsp->vector_fmul_add(out, v + ( 704 >> div), sbr_qmf_window + (320 >> div), out   , 64 >> div);
01222         dsp->vector_fmul_add(out, v + ( 768 >> div), sbr_qmf_window + (384 >> div), out   , 64 >> div);
01223         dsp->vector_fmul_add(out, v + ( 960 >> div), sbr_qmf_window + (448 >> div), out   , 64 >> div);
01224         dsp->vector_fmul_add(out, v + (1024 >> div), sbr_qmf_window + (512 >> div), out   , 64 >> div);
01225         dsp->vector_fmul_add(out, v + (1216 >> div), sbr_qmf_window + (576 >> div), out   , 64 >> div);
01226         out += 64 >> div;
01227     }
01228 }
01229 
01230 static void autocorrelate(const float x[40][2], float phi[3][2][2], int lag)
01231 {
01232     int i;
01233     float real_sum = 0.0f;
01234     float imag_sum = 0.0f;
01235     if (lag) {
01236         for (i = 1; i < 38; i++) {
01237             real_sum += x[i][0] * x[i+lag][0] + x[i][1] * x[i+lag][1];
01238             imag_sum += x[i][0] * x[i+lag][1] - x[i][1] * x[i+lag][0];
01239         }
01240         phi[2-lag][1][0] = real_sum + x[ 0][0] * x[lag][0] + x[ 0][1] * x[lag][1];
01241         phi[2-lag][1][1] = imag_sum + x[ 0][0] * x[lag][1] - x[ 0][1] * x[lag][0];
01242         if (lag == 1) {
01243             phi[0][0][0] = real_sum + x[38][0] * x[39][0] + x[38][1] * x[39][1];
01244             phi[0][0][1] = imag_sum + x[38][0] * x[39][1] - x[38][1] * x[39][0];
01245         }
01246     } else {
01247         for (i = 1; i < 38; i++) {
01248             real_sum += x[i][0] * x[i][0] + x[i][1] * x[i][1];
01249         }
01250         phi[2][1][0] = real_sum + x[ 0][0] * x[ 0][0] + x[ 0][1] * x[ 0][1];
01251         phi[1][0][0] = real_sum + x[38][0] * x[38][0] + x[38][1] * x[38][1];
01252     }
01253 }
01254 
01259 static void sbr_hf_inverse_filter(float (*alpha0)[2], float (*alpha1)[2],
01260                                   const float X_low[32][40][2], int k0)
01261 {
01262     int k;
01263     for (k = 0; k < k0; k++) {
01264         float phi[3][2][2], dk;
01265 
01266         autocorrelate(X_low[k], phi, 0);
01267         autocorrelate(X_low[k], phi, 1);
01268         autocorrelate(X_low[k], phi, 2);
01269 
01270         dk =  phi[2][1][0] * phi[1][0][0] -
01271              (phi[1][1][0] * phi[1][1][0] + phi[1][1][1] * phi[1][1][1]) / 1.000001f;
01272 
01273         if (!dk) {
01274             alpha1[k][0] = 0;
01275             alpha1[k][1] = 0;
01276         } else {
01277             float temp_real, temp_im;
01278             temp_real = phi[0][0][0] * phi[1][1][0] -
01279                         phi[0][0][1] * phi[1][1][1] -
01280                         phi[0][1][0] * phi[1][0][0];
01281             temp_im   = phi[0][0][0] * phi[1][1][1] +
01282                         phi[0][0][1] * phi[1][1][0] -
01283                         phi[0][1][1] * phi[1][0][0];
01284 
01285             alpha1[k][0] = temp_real / dk;
01286             alpha1[k][1] = temp_im   / dk;
01287         }
01288 
01289         if (!phi[1][0][0]) {
01290             alpha0[k][0] = 0;
01291             alpha0[k][1] = 0;
01292         } else {
01293             float temp_real, temp_im;
01294             temp_real = phi[0][0][0] + alpha1[k][0] * phi[1][1][0] +
01295                                        alpha1[k][1] * phi[1][1][1];
01296             temp_im   = phi[0][0][1] + alpha1[k][1] * phi[1][1][0] -
01297                                        alpha1[k][0] * phi[1][1][1];
01298 
01299             alpha0[k][0] = -temp_real / phi[1][0][0];
01300             alpha0[k][1] = -temp_im   / phi[1][0][0];
01301         }
01302 
01303         if (alpha1[k][0] * alpha1[k][0] + alpha1[k][1] * alpha1[k][1] >= 16.0f ||
01304            alpha0[k][0] * alpha0[k][0] + alpha0[k][1] * alpha0[k][1] >= 16.0f) {
01305             alpha1[k][0] = 0;
01306             alpha1[k][1] = 0;
01307             alpha0[k][0] = 0;
01308             alpha0[k][1] = 0;
01309         }
01310     }
01311 }
01312 
01314 static void sbr_chirp(SpectralBandReplication *sbr, SBRData *ch_data)
01315 {
01316     int i;
01317     float new_bw;
01318     static const float bw_tab[] = { 0.0f, 0.75f, 0.9f, 0.98f };
01319 
01320     for (i = 0; i < sbr->n_q; i++) {
01321         if (ch_data->bs_invf_mode[0][i] + ch_data->bs_invf_mode[1][i] == 1) {
01322             new_bw = 0.6f;
01323         } else
01324             new_bw = bw_tab[ch_data->bs_invf_mode[0][i]];
01325 
01326         if (new_bw < ch_data->bw_array[i]) {
01327             new_bw = 0.75f    * new_bw + 0.25f    * ch_data->bw_array[i];
01328         } else
01329             new_bw = 0.90625f * new_bw + 0.09375f * ch_data->bw_array[i];
01330         ch_data->bw_array[i] = new_bw < 0.015625f ? 0.0f : new_bw;
01331     }
01332 }
01333 
01335 static int sbr_lf_gen(AACContext *ac, SpectralBandReplication *sbr,
01336                       float X_low[32][40][2], const float W[2][32][32][2])
01337 {
01338     int i, k;
01339     const int t_HFGen = 8;
01340     const int i_f = 32;
01341     memset(X_low, 0, 32*sizeof(*X_low));
01342     for (k = 0; k < sbr->kx[1]; k++) {
01343         for (i = t_HFGen; i < i_f + t_HFGen; i++) {
01344             X_low[k][i][0] = W[1][i - t_HFGen][k][0];
01345             X_low[k][i][1] = W[1][i - t_HFGen][k][1];
01346         }
01347     }
01348     for (k = 0; k < sbr->kx[0]; k++) {
01349         for (i = 0; i < t_HFGen; i++) {
01350             X_low[k][i][0] = W[0][i + i_f - t_HFGen][k][0];
01351             X_low[k][i][1] = W[0][i + i_f - t_HFGen][k][1];
01352         }
01353     }
01354     return 0;
01355 }
01356 
01358 static int sbr_hf_gen(AACContext *ac, SpectralBandReplication *sbr,
01359                       float X_high[64][40][2], const float X_low[32][40][2],
01360                       const float (*alpha0)[2], const float (*alpha1)[2],
01361                       const float bw_array[5], const uint8_t *t_env,
01362                       int bs_num_env)
01363 {
01364     int i, j, x;
01365     int g = 0;
01366     int k = sbr->kx[1];
01367     for (j = 0; j < sbr->num_patches; j++) {
01368         for (x = 0; x < sbr->patch_num_subbands[j]; x++, k++) {
01369             float alpha[4];
01370             const int p = sbr->patch_start_subband[j] + x;
01371             while (g <= sbr->n_q && k >= sbr->f_tablenoise[g])
01372                 g++;
01373             g--;
01374 
01375             if (g < 0) {
01376                 av_log(ac->avctx, AV_LOG_ERROR,
01377                        "ERROR : no subband found for frequency %d\n", k);
01378                 return -1;
01379             }
01380 
01381             alpha[0] = alpha1[p][0] * bw_array[g] * bw_array[g];
01382             alpha[1] = alpha1[p][1] * bw_array[g] * bw_array[g];
01383             alpha[2] = alpha0[p][0] * bw_array[g];
01384             alpha[3] = alpha0[p][1] * bw_array[g];
01385 
01386             for (i = 2 * t_env[0]; i < 2 * t_env[bs_num_env]; i++) {
01387                 const int idx = i + ENVELOPE_ADJUSTMENT_OFFSET;
01388                 X_high[k][idx][0] =
01389                     X_low[p][idx - 2][0] * alpha[0] -
01390                     X_low[p][idx - 2][1] * alpha[1] +
01391                     X_low[p][idx - 1][0] * alpha[2] -
01392                     X_low[p][idx - 1][1] * alpha[3] +
01393                     X_low[p][idx][0];
01394                 X_high[k][idx][1] =
01395                     X_low[p][idx - 2][1] * alpha[0] +
01396                     X_low[p][idx - 2][0] * alpha[1] +
01397                     X_low[p][idx - 1][1] * alpha[2] +
01398                     X_low[p][idx - 1][0] * alpha[3] +
01399                     X_low[p][idx][1];
01400             }
01401         }
01402     }
01403     if (k < sbr->m[1] + sbr->kx[1])
01404         memset(X_high + k, 0, (sbr->m[1] + sbr->kx[1] - k) * sizeof(*X_high));
01405 
01406     return 0;
01407 }
01408 
01410 static int sbr_x_gen(SpectralBandReplication *sbr, float X[2][38][64],
01411                      const float X_low[32][40][2], const float Y[2][38][64][2],
01412                      int ch)
01413 {
01414     int k, i;
01415     const int i_f = 32;
01416     const int i_Temp = FFMAX(2*sbr->data[ch].t_env_num_env_old - i_f, 0);
01417     memset(X, 0, 2*sizeof(*X));
01418     for (k = 0; k < sbr->kx[0]; k++) {
01419         for (i = 0; i < i_Temp; i++) {
01420             X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
01421             X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
01422         }
01423     }
01424     for (; k < sbr->kx[0] + sbr->m[0]; k++) {
01425         for (i = 0; i < i_Temp; i++) {
01426             X[0][i][k] = Y[0][i + i_f][k][0];
01427             X[1][i][k] = Y[0][i + i_f][k][1];
01428         }
01429     }
01430 
01431     for (k = 0; k < sbr->kx[1]; k++) {
01432         for (i = i_Temp; i < 38; i++) {
01433             X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
01434             X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
01435         }
01436     }
01437     for (; k < sbr->kx[1] + sbr->m[1]; k++) {
01438         for (i = i_Temp; i < i_f; i++) {
01439             X[0][i][k] = Y[1][i][k][0];
01440             X[1][i][k] = Y[1][i][k][1];
01441         }
01442     }
01443     return 0;
01444 }
01445 
01449 static void sbr_mapping(AACContext *ac, SpectralBandReplication *sbr,
01450                         SBRData *ch_data, int e_a[2])
01451 {
01452     int e, i, m;
01453 
01454     memset(ch_data->s_indexmapped[1], 0, 7*sizeof(ch_data->s_indexmapped[1]));
01455     for (e = 0; e < ch_data->bs_num_env; e++) {
01456         const unsigned int ilim = sbr->n[ch_data->bs_freq_res[e + 1]];
01457         uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
01458         int k;
01459 
01460         for (i = 0; i < ilim; i++)
01461             for (m = table[i]; m < table[i + 1]; m++)
01462                 sbr->e_origmapped[e][m - sbr->kx[1]] = ch_data->env_facs[e+1][i];
01463 
01464         // ch_data->bs_num_noise > 1 => 2 noise floors
01465         k = (ch_data->bs_num_noise > 1) && (ch_data->t_env[e] >= ch_data->t_q[1]);
01466         for (i = 0; i < sbr->n_q; i++)
01467             for (m = sbr->f_tablenoise[i]; m < sbr->f_tablenoise[i + 1]; m++)
01468                 sbr->q_mapped[e][m - sbr->kx[1]] = ch_data->noise_facs[k+1][i];
01469 
01470         for (i = 0; i < sbr->n[1]; i++) {
01471             if (ch_data->bs_add_harmonic_flag) {
01472                 const unsigned int m_midpoint =
01473                     (sbr->f_tablehigh[i] + sbr->f_tablehigh[i + 1]) >> 1;
01474 
01475                 ch_data->s_indexmapped[e + 1][m_midpoint - sbr->kx[1]] = ch_data->bs_add_harmonic[i] *
01476                     (e >= e_a[1] || (ch_data->s_indexmapped[0][m_midpoint - sbr->kx[1]] == 1));
01477             }
01478         }
01479 
01480         for (i = 0; i < ilim; i++) {
01481             int additional_sinusoid_present = 0;
01482             for (m = table[i]; m < table[i + 1]; m++) {
01483                 if (ch_data->s_indexmapped[e + 1][m - sbr->kx[1]]) {
01484                     additional_sinusoid_present = 1;
01485                     break;
01486                 }
01487             }
01488             memset(&sbr->s_mapped[e][table[i] - sbr->kx[1]], additional_sinusoid_present,
01489                    (table[i + 1] - table[i]) * sizeof(sbr->s_mapped[e][0]));
01490         }
01491     }
01492 
01493     memcpy(ch_data->s_indexmapped[0], ch_data->s_indexmapped[ch_data->bs_num_env], sizeof(ch_data->s_indexmapped[0]));
01494 }
01495 
01497 static void sbr_env_estimate(float (*e_curr)[48], float X_high[64][40][2],
01498                              SpectralBandReplication *sbr, SBRData *ch_data)
01499 {
01500     int e, i, m;
01501 
01502     if (sbr->bs_interpol_freq) {
01503         for (e = 0; e < ch_data->bs_num_env; e++) {
01504             const float recip_env_size = 0.5f / (ch_data->t_env[e + 1] - ch_data->t_env[e]);
01505             int ilb = ch_data->t_env[e]     * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
01506             int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
01507 
01508             for (m = 0; m < sbr->m[1]; m++) {
01509                 float sum = 0.0f;
01510 
01511                 for (i = ilb; i < iub; i++) {
01512                     sum += X_high[m + sbr->kx[1]][i][0] * X_high[m + sbr->kx[1]][i][0] +
01513                            X_high[m + sbr->kx[1]][i][1] * X_high[m + sbr->kx[1]][i][1];
01514                 }
01515                 e_curr[e][m] = sum * recip_env_size;
01516             }
01517         }
01518     } else {
01519         int k, p;
01520 
01521         for (e = 0; e < ch_data->bs_num_env; e++) {
01522             const int env_size = 2 * (ch_data->t_env[e + 1] - ch_data->t_env[e]);
01523             int ilb = ch_data->t_env[e]     * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
01524             int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
01525             const uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
01526 
01527             for (p = 0; p < sbr->n[ch_data->bs_freq_res[e + 1]]; p++) {
01528                 float sum = 0.0f;
01529                 const int den = env_size * (table[p + 1] - table[p]);
01530 
01531                 for (k = table[p]; k < table[p + 1]; k++) {
01532                     for (i = ilb; i < iub; i++) {
01533                         sum += X_high[k][i][0] * X_high[k][i][0] +
01534                                X_high[k][i][1] * X_high[k][i][1];
01535                     }
01536                 }
01537                 sum /= den;
01538                 for (k = table[p]; k < table[p + 1]; k++) {
01539                     e_curr[e][k - sbr->kx[1]] = sum;
01540                 }
01541             }
01542         }
01543     }
01544 }
01545 
01550 static void sbr_gain_calc(AACContext *ac, SpectralBandReplication *sbr,
01551                           SBRData *ch_data, const int e_a[2])
01552 {
01553     int e, k, m;
01554     // max gain limits : -3dB, 0dB, 3dB, inf dB (limiter off)
01555     static const float limgain[4] = { 0.70795, 1.0, 1.41254, 10000000000 };
01556 
01557     for (e = 0; e < ch_data->bs_num_env; e++) {
01558         int delta = !((e == e_a[1]) || (e == e_a[0]));
01559         for (k = 0; k < sbr->n_lim; k++) {
01560             float gain_boost, gain_max;
01561             float sum[2] = { 0.0f, 0.0f };
01562             for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
01563                 const float temp = sbr->e_origmapped[e][m] / (1.0f + sbr->q_mapped[e][m]);
01564                 sbr->q_m[e][m] = sqrtf(temp * sbr->q_mapped[e][m]);
01565                 sbr->s_m[e][m] = sqrtf(temp * ch_data->s_indexmapped[e + 1][m]);
01566                 if (!sbr->s_mapped[e][m]) {
01567                     sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] /
01568                                             ((1.0f + sbr->e_curr[e][m]) *
01569                                              (1.0f + sbr->q_mapped[e][m] * delta)));
01570                 } else {
01571                     sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] * sbr->q_mapped[e][m] /
01572                                             ((1.0f + sbr->e_curr[e][m]) *
01573                                              (1.0f + sbr->q_mapped[e][m])));
01574                 }
01575             }
01576             for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
01577                 sum[0] += sbr->e_origmapped[e][m];
01578                 sum[1] += sbr->e_curr[e][m];
01579             }
01580             gain_max = limgain[sbr->bs_limiter_gains] * sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
01581             gain_max = FFMIN(100000.f, gain_max);
01582             for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
01583                 float q_m_max   = sbr->q_m[e][m] * gain_max / sbr->gain[e][m];
01584                 sbr->q_m[e][m]  = FFMIN(sbr->q_m[e][m], q_m_max);
01585                 sbr->gain[e][m] = FFMIN(sbr->gain[e][m], gain_max);
01586             }
01587             sum[0] = sum[1] = 0.0f;
01588             for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
01589                 sum[0] += sbr->e_origmapped[e][m];
01590                 sum[1] += sbr->e_curr[e][m] * sbr->gain[e][m] * sbr->gain[e][m]
01591                           + sbr->s_m[e][m] * sbr->s_m[e][m]
01592                           + (delta && !sbr->s_m[e][m]) * sbr->q_m[e][m] * sbr->q_m[e][m];
01593             }
01594             gain_boost = sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
01595             gain_boost = FFMIN(1.584893192f, gain_boost);
01596             for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
01597                 sbr->gain[e][m] *= gain_boost;
01598                 sbr->q_m[e][m]  *= gain_boost;
01599                 sbr->s_m[e][m]  *= gain_boost;
01600             }
01601         }
01602     }
01603 }
01604 
01606 static void sbr_hf_assemble(float Y[2][38][64][2], const float X_high[64][40][2],
01607                             SpectralBandReplication *sbr, SBRData *ch_data,
01608                             const int e_a[2])
01609 {
01610     int e, i, j, m;
01611     const int h_SL = 4 * !sbr->bs_smoothing_mode;
01612     const int kx = sbr->kx[1];
01613     const int m_max = sbr->m[1];
01614     static const float h_smooth[5] = {
01615         0.33333333333333,
01616         0.30150283239582,
01617         0.21816949906249,
01618         0.11516383427084,
01619         0.03183050093751,
01620     };
01621     static const int8_t phi[2][4] = {
01622         {  1,  0, -1,  0}, // real
01623         {  0,  1,  0, -1}, // imaginary
01624     };
01625     float (*g_temp)[48] = ch_data->g_temp, (*q_temp)[48] = ch_data->q_temp;
01626     int indexnoise = ch_data->f_indexnoise;
01627     int indexsine  = ch_data->f_indexsine;
01628     memcpy(Y[0], Y[1], sizeof(Y[0]));
01629 
01630     if (sbr->reset) {
01631         for (i = 0; i < h_SL; i++) {
01632             memcpy(g_temp[i + 2*ch_data->t_env[0]], sbr->gain[0], m_max * sizeof(sbr->gain[0][0]));
01633             memcpy(q_temp[i + 2*ch_data->t_env[0]], sbr->q_m[0],  m_max * sizeof(sbr->q_m[0][0]));
01634         }
01635     } else if (h_SL) {
01636         memcpy(g_temp[2*ch_data->t_env[0]], g_temp[2*ch_data->t_env_num_env_old], 4*sizeof(g_temp[0]));
01637         memcpy(q_temp[2*ch_data->t_env[0]], q_temp[2*ch_data->t_env_num_env_old], 4*sizeof(q_temp[0]));
01638     }
01639 
01640     for (e = 0; e < ch_data->bs_num_env; e++) {
01641         for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
01642             memcpy(g_temp[h_SL + i], sbr->gain[e], m_max * sizeof(sbr->gain[0][0]));
01643             memcpy(q_temp[h_SL + i], sbr->q_m[e],  m_max * sizeof(sbr->q_m[0][0]));
01644         }
01645     }
01646 
01647     for (e = 0; e < ch_data->bs_num_env; e++) {
01648         for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
01649             int phi_sign = (1 - 2*(kx & 1));
01650 
01651             if (h_SL && e != e_a[0] && e != e_a[1]) {
01652                 for (m = 0; m < m_max; m++) {
01653                     const int idx1 = i + h_SL;
01654                     float g_filt = 0.0f;
01655                     for (j = 0; j <= h_SL; j++)
01656                         g_filt += g_temp[idx1 - j][m] * h_smooth[j];
01657                     Y[1][i][m + kx][0] =
01658                         X_high[m + kx][i + ENVELOPE_ADJUSTMENT_OFFSET][0] * g_filt;
01659                     Y[1][i][m + kx][1] =
01660                         X_high[m + kx][i + ENVELOPE_ADJUSTMENT_OFFSET][1] * g_filt;
01661                 }
01662             } else {
01663                 for (m = 0; m < m_max; m++) {
01664                     const float g_filt = g_temp[i + h_SL][m];
01665                     Y[1][i][m + kx][0] =
01666                         X_high[m + kx][i + ENVELOPE_ADJUSTMENT_OFFSET][0] * g_filt;
01667                     Y[1][i][m + kx][1] =
01668                         X_high[m + kx][i + ENVELOPE_ADJUSTMENT_OFFSET][1] * g_filt;
01669                 }
01670             }
01671 
01672             if (e != e_a[0] && e != e_a[1]) {
01673                 for (m = 0; m < m_max; m++) {
01674                     indexnoise = (indexnoise + 1) & 0x1ff;
01675                     if (sbr->s_m[e][m]) {
01676                         Y[1][i][m + kx][0] +=
01677                             sbr->s_m[e][m] * phi[0][indexsine];
01678                         Y[1][i][m + kx][1] +=
01679                             sbr->s_m[e][m] * (phi[1][indexsine] * phi_sign);
01680                     } else {
01681                         float q_filt;
01682                         if (h_SL) {
01683                             const int idx1 = i + h_SL;
01684                             q_filt = 0.0f;
01685                             for (j = 0; j <= h_SL; j++)
01686                                 q_filt += q_temp[idx1 - j][m] * h_smooth[j];
01687                         } else {
01688                             q_filt = q_temp[i][m];
01689                         }
01690                         Y[1][i][m + kx][0] +=
01691                             q_filt * sbr_noise_table[indexnoise][0];
01692                         Y[1][i][m + kx][1] +=
01693                             q_filt * sbr_noise_table[indexnoise][1];
01694                     }
01695                     phi_sign = -phi_sign;
01696                 }
01697             } else {
01698                 indexnoise = (indexnoise + m_max) & 0x1ff;
01699                 for (m = 0; m < m_max; m++) {
01700                     Y[1][i][m + kx][0] +=
01701                         sbr->s_m[e][m] * phi[0][indexsine];
01702                     Y[1][i][m + kx][1] +=
01703                         sbr->s_m[e][m] * (phi[1][indexsine] * phi_sign);
01704                     phi_sign = -phi_sign;
01705                 }
01706             }
01707             indexsine = (indexsine + 1) & 3;
01708         }
01709     }
01710     ch_data->f_indexnoise = indexnoise;
01711     ch_data->f_indexsine  = indexsine;
01712 }
01713 
01714 void ff_sbr_apply(AACContext *ac, SpectralBandReplication *sbr, int id_aac,
01715                   float* L, float* R)
01716 {
01717     int downsampled = ac->m4ac.ext_sample_rate < sbr->sample_rate;
01718     int ch;
01719     int nch = (id_aac == TYPE_CPE) ? 2 : 1;
01720 
01721     if (sbr->start) {
01722         sbr_dequant(sbr, id_aac);
01723     }
01724     for (ch = 0; ch < nch; ch++) {
01725         /* decode channel */
01726         sbr_qmf_analysis(&ac->dsp, &sbr->mdct_ana, ch ? R : L, sbr->data[ch].analysis_filterbank_samples,
01727                          (float*)sbr->qmf_filter_scratch,
01728                          sbr->data[ch].W);
01729         sbr_lf_gen(ac, sbr, sbr->X_low, sbr->data[ch].W);
01730         if (sbr->start) {
01731             sbr_hf_inverse_filter(sbr->alpha0, sbr->alpha1, sbr->X_low, sbr->k[0]);
01732             sbr_chirp(sbr, &sbr->data[ch]);
01733             sbr_hf_gen(ac, sbr, sbr->X_high, sbr->X_low, sbr->alpha0, sbr->alpha1,
01734                        sbr->data[ch].bw_array, sbr->data[ch].t_env,
01735                        sbr->data[ch].bs_num_env);
01736 
01737             // hf_adj
01738             sbr_mapping(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
01739             sbr_env_estimate(sbr->e_curr, sbr->X_high, sbr, &sbr->data[ch]);
01740             sbr_gain_calc(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
01741             sbr_hf_assemble(sbr->data[ch].Y, sbr->X_high, sbr, &sbr->data[ch],
01742                             sbr->data[ch].e_a);
01743         }
01744 
01745         /* synthesis */
01746         sbr_x_gen(sbr, sbr->X[ch], sbr->X_low, sbr->data[ch].Y, ch);
01747     }
01748 
01749     if (ac->m4ac.ps == 1) {
01750         if (sbr->ps.start) {
01751             ff_ps_apply(ac->avctx, &sbr->ps, sbr->X[0], sbr->X[1], sbr->kx[1] + sbr->m[1]);
01752         } else {
01753             memcpy(sbr->X[1], sbr->X[0], sizeof(sbr->X[0]));
01754         }
01755         nch = 2;
01756     }
01757 
01758     sbr_qmf_synthesis(&ac->dsp, &sbr->mdct, L, sbr->X[0], sbr->qmf_filter_scratch,
01759                       sbr->data[0].synthesis_filterbank_samples,
01760                       &sbr->data[0].synthesis_filterbank_samples_offset,
01761                       downsampled);
01762     if (nch == 2)
01763         sbr_qmf_synthesis(&ac->dsp, &sbr->mdct, R, sbr->X[1], sbr->qmf_filter_scratch,
01764                           sbr->data[1].synthesis_filterbank_samples,
01765                           &sbr->data[1].synthesis_filterbank_samples_offset,
01766                           downsampled);
01767 }
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