Libav

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 FFmpeg.
00007  *
00008  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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(SpectralBandReplication *sbr)
00130 {
00131     sbr->kx[0] = sbr->kx[1] = 32; //Typo in spec, kx' inits to 32
00132     sbr->data[0].e_a[1] = sbr->data[1].e_a[1] = -1;
00133     sbr->data[0].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
00134     sbr->data[1].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
00135     ff_mdct_init(&sbr->mdct, 7, 1, 1.0/64);
00136     ff_mdct_init(&sbr->mdct_ana, 7, 1, -2.0);
00137     ff_ps_ctx_init(&sbr->ps);
00138 }
00139 
00140 av_cold void ff_aac_sbr_ctx_close(SpectralBandReplication *sbr)
00141 {
00142     ff_mdct_end(&sbr->mdct);
00143     ff_mdct_end(&sbr->mdct_ana);
00144 }
00145 
00146 static int qsort_comparison_function_int16(const void *a, const void *b)
00147 {
00148     return *(const int16_t *)a - *(const int16_t *)b;
00149 }
00150 
00151 static inline int in_table_int16(const int16_t *table, int last_el, int16_t needle)
00152 {
00153     int i;
00154     for (i = 0; i <= last_el; i++)
00155         if (table[i] == needle)
00156             return 1;
00157     return 0;
00158 }
00159 
00161 static void sbr_make_f_tablelim(SpectralBandReplication *sbr)
00162 {
00163     int k;
00164     if (sbr->bs_limiter_bands > 0) {
00165         static const float bands_warped[3] = { 1.32715174233856803909f,   //2^(0.49/1.2)
00166                                                1.18509277094158210129f,   //2^(0.49/2)
00167                                                1.11987160404675912501f }; //2^(0.49/3)
00168         const float lim_bands_per_octave_warped = bands_warped[sbr->bs_limiter_bands - 1];
00169         int16_t patch_borders[7];
00170         uint16_t *in = sbr->f_tablelim + 1, *out = sbr->f_tablelim;
00171 
00172         patch_borders[0] = sbr->kx[1];
00173         for (k = 1; k <= sbr->num_patches; k++)
00174             patch_borders[k] = patch_borders[k-1] + sbr->patch_num_subbands[k-1];
00175 
00176         memcpy(sbr->f_tablelim, sbr->f_tablelow,
00177                (sbr->n[0] + 1) * sizeof(sbr->f_tablelow[0]));
00178         if (sbr->num_patches > 1)
00179             memcpy(sbr->f_tablelim + sbr->n[0] + 1, patch_borders + 1,
00180                    (sbr->num_patches - 1) * sizeof(patch_borders[0]));
00181 
00182         qsort(sbr->f_tablelim, sbr->num_patches + sbr->n[0],
00183               sizeof(sbr->f_tablelim[0]),
00184               qsort_comparison_function_int16);
00185 
00186         sbr->n_lim = sbr->n[0] + sbr->num_patches - 1;
00187         while (out < sbr->f_tablelim + sbr->n_lim) {
00188             if (*in >= *out * lim_bands_per_octave_warped) {
00189                 *++out = *in++;
00190             } else if (*in == *out ||
00191                 !in_table_int16(patch_borders, sbr->num_patches, *in)) {
00192                 in++;
00193                 sbr->n_lim--;
00194             } else if (!in_table_int16(patch_borders, sbr->num_patches, *out)) {
00195                 *out = *in++;
00196                 sbr->n_lim--;
00197             } else {
00198                 *++out = *in++;
00199             }
00200         }
00201     } else {
00202         sbr->f_tablelim[0] = sbr->f_tablelow[0];
00203         sbr->f_tablelim[1] = sbr->f_tablelow[sbr->n[0]];
00204         sbr->n_lim = 1;
00205     }
00206 }
00207 
00208 static unsigned int read_sbr_header(SpectralBandReplication *sbr, GetBitContext *gb)
00209 {
00210     unsigned int cnt = get_bits_count(gb);
00211     uint8_t bs_header_extra_1;
00212     uint8_t bs_header_extra_2;
00213     int old_bs_limiter_bands = sbr->bs_limiter_bands;
00214     SpectrumParameters old_spectrum_params;
00215 
00216     sbr->start = 1;
00217 
00218     // Save last spectrum parameters variables to compare to new ones
00219     memcpy(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters));
00220 
00221     sbr->bs_amp_res_header              = get_bits1(gb);
00222     sbr->spectrum_params.bs_start_freq  = get_bits(gb, 4);
00223     sbr->spectrum_params.bs_stop_freq   = get_bits(gb, 4);
00224     sbr->spectrum_params.bs_xover_band  = get_bits(gb, 3);
00225                                           skip_bits(gb, 2); // bs_reserved
00226 
00227     bs_header_extra_1 = get_bits1(gb);
00228     bs_header_extra_2 = get_bits1(gb);
00229 
00230     if (bs_header_extra_1) {
00231         sbr->spectrum_params.bs_freq_scale  = get_bits(gb, 2);
00232         sbr->spectrum_params.bs_alter_scale = get_bits1(gb);
00233         sbr->spectrum_params.bs_noise_bands = get_bits(gb, 2);
00234     } else {
00235         sbr->spectrum_params.bs_freq_scale  = 2;
00236         sbr->spectrum_params.bs_alter_scale = 1;
00237         sbr->spectrum_params.bs_noise_bands = 2;
00238     }
00239 
00240     // Check if spectrum parameters changed
00241     if (memcmp(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters)))
00242         sbr->reset = 1;
00243 
00244     if (bs_header_extra_2) {
00245         sbr->bs_limiter_bands  = get_bits(gb, 2);
00246         sbr->bs_limiter_gains  = get_bits(gb, 2);
00247         sbr->bs_interpol_freq  = get_bits1(gb);
00248         sbr->bs_smoothing_mode = get_bits1(gb);
00249     } else {
00250         sbr->bs_limiter_bands  = 2;
00251         sbr->bs_limiter_gains  = 2;
00252         sbr->bs_interpol_freq  = 1;
00253         sbr->bs_smoothing_mode = 1;
00254     }
00255 
00256     if (sbr->bs_limiter_bands != old_bs_limiter_bands && !sbr->reset)
00257         sbr_make_f_tablelim(sbr);
00258 
00259     return get_bits_count(gb) - cnt;
00260 }
00261 
00262 static int array_min_int16(const int16_t *array, int nel)
00263 {
00264     int i, min = array[0];
00265     for (i = 1; i < nel; i++)
00266         min = FFMIN(array[i], min);
00267     return min;
00268 }
00269 
00270 static void make_bands(int16_t* bands, int start, int stop, int num_bands)
00271 {
00272     int k, previous, present;
00273     float base, prod;
00274 
00275     base = powf((float)stop / start, 1.0f / num_bands);
00276     prod = start;
00277     previous = start;
00278 
00279     for (k = 0; k < num_bands-1; k++) {
00280         prod *= base;
00281         present  = lrintf(prod);
00282         bands[k] = present - previous;
00283         previous = present;
00284     }
00285     bands[num_bands-1] = stop - previous;
00286 }
00287 
00288 static int check_n_master(AVCodecContext *avctx, int n_master, int bs_xover_band)
00289 {
00290     // Requirements (14496-3 sp04 p205)
00291     if (n_master <= 0) {
00292         av_log(avctx, AV_LOG_ERROR, "Invalid n_master: %d\n", n_master);
00293         return -1;
00294     }
00295     if (bs_xover_band >= n_master) {
00296         av_log(avctx, AV_LOG_ERROR,
00297                "Invalid bitstream, crossover band index beyond array bounds: %d\n",
00298                bs_xover_band);
00299         return -1;
00300     }
00301     return 0;
00302 }
00303 
00305 static int sbr_make_f_master(AACContext *ac, SpectralBandReplication *sbr,
00306                              SpectrumParameters *spectrum)
00307 {
00308     unsigned int temp, max_qmf_subbands;
00309     unsigned int start_min, stop_min;
00310     int k;
00311     const int8_t *sbr_offset_ptr;
00312     int16_t stop_dk[13];
00313 
00314     if (sbr->sample_rate < 32000) {
00315         temp = 3000;
00316     } else if (sbr->sample_rate < 64000) {
00317         temp = 4000;
00318     } else
00319         temp = 5000;
00320 
00321     start_min = ((temp << 7) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
00322     stop_min  = ((temp << 8) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
00323 
00324     switch (sbr->sample_rate) {
00325     case 16000:
00326         sbr_offset_ptr = sbr_offset[0];
00327         break;
00328     case 22050:
00329         sbr_offset_ptr = sbr_offset[1];
00330         break;
00331     case 24000:
00332         sbr_offset_ptr = sbr_offset[2];
00333         break;
00334     case 32000:
00335         sbr_offset_ptr = sbr_offset[3];
00336         break;
00337     case 44100: case 48000: case 64000:
00338         sbr_offset_ptr = sbr_offset[4];
00339         break;
00340     case 88200: case 96000: case 128000: case 176400: case 192000:
00341         sbr_offset_ptr = sbr_offset[5];
00342         break;
00343     default:
00344         av_log(ac->avctx, AV_LOG_ERROR,
00345                "Unsupported sample rate for SBR: %d\n", sbr->sample_rate);
00346         return -1;
00347     }
00348 
00349     sbr->k[0] = start_min + sbr_offset_ptr[spectrum->bs_start_freq];
00350 
00351     if (spectrum->bs_stop_freq < 14) {
00352         sbr->k[2] = stop_min;
00353         make_bands(stop_dk, stop_min, 64, 13);
00354         qsort(stop_dk, 13, sizeof(stop_dk[0]), qsort_comparison_function_int16);
00355         for (k = 0; k < spectrum->bs_stop_freq; k++)
00356             sbr->k[2] += stop_dk[k];
00357     } else if (spectrum->bs_stop_freq == 14) {
00358         sbr->k[2] = 2*sbr->k[0];
00359     } else if (spectrum->bs_stop_freq == 15) {
00360         sbr->k[2] = 3*sbr->k[0];
00361     } else {
00362         av_log(ac->avctx, AV_LOG_ERROR,
00363                "Invalid bs_stop_freq: %d\n", spectrum->bs_stop_freq);
00364         return -1;
00365     }
00366     sbr->k[2] = FFMIN(64, sbr->k[2]);
00367 
00368     // Requirements (14496-3 sp04 p205)
00369     if (sbr->sample_rate <= 32000) {
00370         max_qmf_subbands = 48;
00371     } else if (sbr->sample_rate == 44100) {
00372         max_qmf_subbands = 35;
00373     } else if (sbr->sample_rate >= 48000)
00374         max_qmf_subbands = 32;
00375 
00376     if (sbr->k[2] - sbr->k[0] > max_qmf_subbands) {
00377         av_log(ac->avctx, AV_LOG_ERROR,
00378                "Invalid bitstream, too many QMF subbands: %d\n", sbr->k[2] - sbr->k[0]);
00379         return -1;
00380     }
00381 
00382     if (!spectrum->bs_freq_scale) {
00383         int dk, k2diff;
00384 
00385         dk = spectrum->bs_alter_scale + 1;
00386         sbr->n_master = ((sbr->k[2] - sbr->k[0] + (dk&2)) >> dk) << 1;
00387         if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
00388             return -1;
00389 
00390         for (k = 1; k <= sbr->n_master; k++)
00391             sbr->f_master[k] = dk;
00392 
00393         k2diff = sbr->k[2] - sbr->k[0] - sbr->n_master * dk;
00394         if (k2diff < 0) {
00395             sbr->f_master[1]--;
00396             sbr->f_master[2]-= (k2diff < -1);
00397         } else if (k2diff) {
00398             sbr->f_master[sbr->n_master]++;
00399         }
00400 
00401         sbr->f_master[0] = sbr->k[0];
00402         for (k = 1; k <= sbr->n_master; k++)
00403             sbr->f_master[k] += sbr->f_master[k - 1];
00404 
00405     } else {
00406         int half_bands = 7 - spectrum->bs_freq_scale;      // bs_freq_scale  = {1,2,3}
00407         int two_regions, num_bands_0;
00408         int vdk0_max, vdk1_min;
00409         int16_t vk0[49];
00410 
00411         if (49 * sbr->k[2] > 110 * sbr->k[0]) {
00412             two_regions = 1;
00413             sbr->k[1] = 2 * sbr->k[0];
00414         } else {
00415             two_regions = 0;
00416             sbr->k[1] = sbr->k[2];
00417         }
00418 
00419         num_bands_0 = lrintf(half_bands * log2f(sbr->k[1] / (float)sbr->k[0])) * 2;
00420 
00421         if (num_bands_0 <= 0) { // Requirements (14496-3 sp04 p205)
00422             av_log(ac->avctx, AV_LOG_ERROR, "Invalid num_bands_0: %d\n", num_bands_0);
00423             return -1;
00424         }
00425 
00426         vk0[0] = 0;
00427 
00428         make_bands(vk0+1, sbr->k[0], sbr->k[1], num_bands_0);
00429 
00430         qsort(vk0 + 1, num_bands_0, sizeof(vk0[1]), qsort_comparison_function_int16);
00431         vdk0_max = vk0[num_bands_0];
00432 
00433         vk0[0] = sbr->k[0];
00434         for (k = 1; k <= num_bands_0; k++) {
00435             if (vk0[k] <= 0) { // Requirements (14496-3 sp04 p205)
00436                 av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk0[%d]: %d\n", k, vk0[k]);
00437                 return -1;
00438             }
00439             vk0[k] += vk0[k-1];
00440         }
00441 
00442         if (two_regions) {
00443             int16_t vk1[49];
00444             float invwarp = spectrum->bs_alter_scale ? 0.76923076923076923077f
00445                                                      : 1.0f; // bs_alter_scale = {0,1}
00446             int num_bands_1 = lrintf(half_bands * invwarp *
00447                                      log2f(sbr->k[2] / (float)sbr->k[1])) * 2;
00448 
00449             make_bands(vk1+1, sbr->k[1], sbr->k[2], num_bands_1);
00450 
00451             vdk1_min = array_min_int16(vk1 + 1, num_bands_1);
00452 
00453             if (vdk1_min < vdk0_max) {
00454                 int change;
00455                 qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
00456                 change = FFMIN(vdk0_max - vk1[1], (vk1[num_bands_1] - vk1[1]) >> 1);
00457                 vk1[1]           += change;
00458                 vk1[num_bands_1] -= change;
00459             }
00460 
00461             qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
00462 
00463             vk1[0] = sbr->k[1];
00464             for (k = 1; k <= num_bands_1; k++) {
00465                 if (vk1[k] <= 0) { // Requirements (14496-3 sp04 p205)
00466                     av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk1[%d]: %d\n", k, vk1[k]);
00467                     return -1;
00468                 }
00469                 vk1[k] += vk1[k-1];
00470             }
00471 
00472             sbr->n_master = num_bands_0 + num_bands_1;
00473             if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
00474                 return -1;
00475             memcpy(&sbr->f_master[0],               vk0,
00476                    (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
00477             memcpy(&sbr->f_master[num_bands_0 + 1], vk1 + 1,
00478                     num_bands_1      * sizeof(sbr->f_master[0]));
00479 
00480         } else {
00481             sbr->n_master = num_bands_0;
00482             if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
00483                 return -1;
00484             memcpy(sbr->f_master, vk0, (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
00485         }
00486     }
00487 
00488     return 0;
00489 }
00490 
00492 static int sbr_hf_calc_npatches(AACContext *ac, SpectralBandReplication *sbr)
00493 {
00494     int i, k, sb = 0;
00495     int msb = sbr->k[0];
00496     int usb = sbr->kx[1];
00497     int goal_sb = ((1000 << 11) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
00498 
00499     sbr->num_patches = 0;
00500 
00501     if (goal_sb < sbr->kx[1] + sbr->m[1]) {
00502         for (k = 0; sbr->f_master[k] < goal_sb; k++) ;
00503     } else
00504         k = sbr->n_master;
00505 
00506     do {
00507         int odd = 0;
00508         for (i = k; i == k || sb > (sbr->k[0] - 1 + msb - odd); i--) {
00509             sb = sbr->f_master[i];
00510             odd = (sb + sbr->k[0]) & 1;
00511         }
00512 
00513         // Requirements (14496-3 sp04 p205) sets the maximum number of patches to 5.
00514         // After this check the final number of patches can still be six which is
00515         // illegal however the Coding Technologies decoder check stream has a final
00516         // count of 6 patches
00517         if (sbr->num_patches > 5) {
00518             av_log(ac->avctx, AV_LOG_ERROR, "Too many patches: %d\n", sbr->num_patches);
00519             return -1;
00520         }
00521 
00522         sbr->patch_num_subbands[sbr->num_patches]  = FFMAX(sb - usb, 0);
00523         sbr->patch_start_subband[sbr->num_patches] = sbr->k[0] - odd - sbr->patch_num_subbands[sbr->num_patches];
00524 
00525         if (sbr->patch_num_subbands[sbr->num_patches] > 0) {
00526             usb = sb;
00527             msb = sb;
00528             sbr->num_patches++;
00529         } else
00530             msb = sbr->kx[1];
00531 
00532         if (sbr->f_master[k] - sb < 3)
00533             k = sbr->n_master;
00534     } while (sb != sbr->kx[1] + sbr->m[1]);
00535 
00536     if (sbr->patch_num_subbands[sbr->num_patches-1] < 3 && sbr->num_patches > 1)
00537         sbr->num_patches--;
00538 
00539     return 0;
00540 }
00541 
00543 static int sbr_make_f_derived(AACContext *ac, SpectralBandReplication *sbr)
00544 {
00545     int k, temp;
00546 
00547     sbr->n[1] = sbr->n_master - sbr->spectrum_params.bs_xover_band;
00548     sbr->n[0] = (sbr->n[1] + 1) >> 1;
00549 
00550     memcpy(sbr->f_tablehigh, &sbr->f_master[sbr->spectrum_params.bs_xover_band],
00551            (sbr->n[1] + 1) * sizeof(sbr->f_master[0]));
00552     sbr->m[1] = sbr->f_tablehigh[sbr->n[1]] - sbr->f_tablehigh[0];
00553     sbr->kx[1] = sbr->f_tablehigh[0];
00554 
00555     // Requirements (14496-3 sp04 p205)
00556     if (sbr->kx[1] + sbr->m[1] > 64) {
00557         av_log(ac->avctx, AV_LOG_ERROR,
00558                "Stop frequency border too high: %d\n", sbr->kx[1] + sbr->m[1]);
00559         return -1;
00560     }
00561     if (sbr->kx[1] > 32) {
00562         av_log(ac->avctx, AV_LOG_ERROR, "Start frequency border too high: %d\n", sbr->kx[1]);
00563         return -1;
00564     }
00565 
00566     sbr->f_tablelow[0] = sbr->f_tablehigh[0];
00567     temp = sbr->n[1] & 1;
00568     for (k = 1; k <= sbr->n[0]; k++)
00569         sbr->f_tablelow[k] = sbr->f_tablehigh[2 * k - temp];
00570 
00571     sbr->n_q = FFMAX(1, lrintf(sbr->spectrum_params.bs_noise_bands *
00572                                log2f(sbr->k[2] / (float)sbr->kx[1]))); // 0 <= bs_noise_bands <= 3
00573     if (sbr->n_q > 5) {
00574         av_log(ac->avctx, AV_LOG_ERROR, "Too many noise floor scale factors: %d\n", sbr->n_q);
00575         return -1;
00576     }
00577 
00578     sbr->f_tablenoise[0] = sbr->f_tablelow[0];
00579     temp = 0;
00580     for (k = 1; k <= sbr->n_q; k++) {
00581         temp += (sbr->n[0] - temp) / (sbr->n_q + 1 - k);
00582         sbr->f_tablenoise[k] = sbr->f_tablelow[temp];
00583     }
00584 
00585     if (sbr_hf_calc_npatches(ac, sbr) < 0)
00586         return -1;
00587 
00588     sbr_make_f_tablelim(sbr);
00589 
00590     sbr->data[0].f_indexnoise = 0;
00591     sbr->data[1].f_indexnoise = 0;
00592 
00593     return 0;
00594 }
00595 
00596 static av_always_inline void get_bits1_vector(GetBitContext *gb, uint8_t *vec,
00597                                               int elements)
00598 {
00599     int i;
00600     for (i = 0; i < elements; i++) {
00601         vec[i] = get_bits1(gb);
00602     }
00603 }
00604 
00606 static const int8_t ceil_log2[] = {
00607     0, 1, 2, 2, 3, 3,
00608 };
00609 
00610 static int read_sbr_grid(AACContext *ac, SpectralBandReplication *sbr,
00611                          GetBitContext *gb, SBRData *ch_data)
00612 {
00613     int i;
00614     unsigned bs_pointer = 0;
00615     // frameLengthFlag ? 15 : 16; 960 sample length frames unsupported; this value is numTimeSlots
00616     int abs_bord_trail = 16;
00617     int num_rel_lead, num_rel_trail;
00618     unsigned bs_num_env_old = ch_data->bs_num_env;
00619 
00620     ch_data->bs_freq_res[0] = ch_data->bs_freq_res[ch_data->bs_num_env];
00621     ch_data->bs_amp_res = sbr->bs_amp_res_header;
00622     ch_data->t_env_num_env_old = ch_data->t_env[bs_num_env_old];
00623 
00624     switch (ch_data->bs_frame_class = get_bits(gb, 2)) {
00625     case FIXFIX:
00626         ch_data->bs_num_env                 = 1 << get_bits(gb, 2);
00627         num_rel_lead                        = ch_data->bs_num_env - 1;
00628         if (ch_data->bs_num_env == 1)
00629             ch_data->bs_amp_res = 0;
00630 
00631         if (ch_data->bs_num_env > 4) {
00632             av_log(ac->avctx, AV_LOG_ERROR,
00633                    "Invalid bitstream, too many SBR envelopes in FIXFIX type SBR frame: %d\n",
00634                    ch_data->bs_num_env);
00635             return -1;
00636         }
00637 
00638         ch_data->t_env[0]                   = 0;
00639         ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
00640 
00641         abs_bord_trail = (abs_bord_trail + (ch_data->bs_num_env >> 1)) /
00642                    ch_data->bs_num_env;
00643         for (i = 0; i < num_rel_lead; i++)
00644             ch_data->t_env[i + 1] = ch_data->t_env[i] + abs_bord_trail;
00645 
00646         ch_data->bs_freq_res[1] = get_bits1(gb);
00647         for (i = 1; i < ch_data->bs_num_env; i++)
00648             ch_data->bs_freq_res[i + 1] = ch_data->bs_freq_res[1];
00649         break;
00650     case FIXVAR:
00651         abs_bord_trail                     += get_bits(gb, 2);
00652         num_rel_trail                       = get_bits(gb, 2);
00653         ch_data->bs_num_env                 = num_rel_trail + 1;
00654         ch_data->t_env[0]                   = 0;
00655         ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
00656 
00657         for (i = 0; i < num_rel_trail; i++)
00658             ch_data->t_env[ch_data->bs_num_env - 1 - i] =
00659                 ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
00660 
00661         bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
00662 
00663         for (i = 0; i < ch_data->bs_num_env; i++)
00664             ch_data->bs_freq_res[ch_data->bs_num_env - i] = get_bits1(gb);
00665         break;
00666     case VARFIX:
00667         ch_data->t_env[0]                   = get_bits(gb, 2);
00668         num_rel_lead                        = get_bits(gb, 2);
00669         ch_data->bs_num_env                 = num_rel_lead + 1;
00670         ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
00671 
00672         for (i = 0; i < num_rel_lead; i++)
00673             ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
00674 
00675         bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
00676 
00677         get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
00678         break;
00679     case VARVAR:
00680         ch_data->t_env[0]                   = get_bits(gb, 2);
00681         abs_bord_trail                     += get_bits(gb, 2);
00682         num_rel_lead                        = get_bits(gb, 2);
00683         num_rel_trail                       = get_bits(gb, 2);
00684         ch_data->bs_num_env                 = num_rel_lead + num_rel_trail + 1;
00685 
00686         if (ch_data->bs_num_env > 5) {
00687             av_log(ac->avctx, AV_LOG_ERROR,
00688                    "Invalid bitstream, too many SBR envelopes in VARVAR type SBR frame: %d\n",
00689                    ch_data->bs_num_env);
00690             return -1;
00691         }
00692 
00693         ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
00694 
00695         for (i = 0; i < num_rel_lead; i++)
00696             ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
00697         for (i = 0; i < num_rel_trail; i++)
00698             ch_data->t_env[ch_data->bs_num_env - 1 - i] =
00699                 ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
00700 
00701         bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
00702 
00703         get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
00704         break;
00705     }
00706 
00707     if (bs_pointer > ch_data->bs_num_env + 1) {
00708         av_log(ac->avctx, AV_LOG_ERROR,
00709                "Invalid bitstream, bs_pointer points to a middle noise border outside the time borders table: %d\n",
00710                bs_pointer);
00711         return -1;
00712     }
00713 
00714     for (i = 1; i <= ch_data->bs_num_env; i++) {
00715         if (ch_data->t_env[i-1] > ch_data->t_env[i]) {
00716             av_log(ac->avctx, AV_LOG_ERROR, "Non monotone time borders\n");
00717             return -1;
00718         }
00719     }
00720 
00721     ch_data->bs_num_noise = (ch_data->bs_num_env > 1) + 1;
00722 
00723     ch_data->t_q[0]                     = ch_data->t_env[0];
00724     ch_data->t_q[ch_data->bs_num_noise] = ch_data->t_env[ch_data->bs_num_env];
00725     if (ch_data->bs_num_noise > 1) {
00726         unsigned int idx;
00727         if (ch_data->bs_frame_class == FIXFIX) {
00728             idx = ch_data->bs_num_env >> 1;
00729         } else if (ch_data->bs_frame_class & 1) { // FIXVAR or VARVAR
00730             idx = ch_data->bs_num_env - FFMAX(bs_pointer - 1, 1);
00731         } else { // VARFIX
00732             if (!bs_pointer)
00733                 idx = 1;
00734             else if (bs_pointer == 1)
00735                 idx = ch_data->bs_num_env - 1;
00736             else // bs_pointer > 1
00737                 idx = bs_pointer - 1;
00738         }
00739         ch_data->t_q[1] = ch_data->t_env[idx];
00740     }
00741 
00742     ch_data->e_a[0] = -(ch_data->e_a[1] != bs_num_env_old); // l_APrev
00743     ch_data->e_a[1] = -1;
00744     if ((ch_data->bs_frame_class & 1) && bs_pointer) { // FIXVAR or VARVAR and bs_pointer != 0
00745         ch_data->e_a[1] = ch_data->bs_num_env + 1 - bs_pointer;
00746     } else if ((ch_data->bs_frame_class == 2) && (bs_pointer > 1)) // VARFIX and bs_pointer > 1
00747         ch_data->e_a[1] = bs_pointer - 1;
00748 
00749     return 0;
00750 }
00751 
00752 static void copy_sbr_grid(SBRData *dst, const SBRData *src) {
00753     //These variables are saved from the previous frame rather than copied
00754     dst->bs_freq_res[0]    = dst->bs_freq_res[dst->bs_num_env];
00755     dst->t_env_num_env_old = dst->t_env[dst->bs_num_env];
00756     dst->e_a[0]            = -(dst->e_a[1] != dst->bs_num_env);
00757 
00758     //These variables are read from the bitstream and therefore copied
00759     memcpy(dst->bs_freq_res+1, src->bs_freq_res+1, sizeof(dst->bs_freq_res)-sizeof(*dst->bs_freq_res));
00760     memcpy(dst->t_env,         src->t_env,         sizeof(dst->t_env));
00761     memcpy(dst->t_q,           src->t_q,           sizeof(dst->t_q));
00762     dst->bs_num_env        = src->bs_num_env;
00763     dst->bs_amp_res        = src->bs_amp_res;
00764     dst->bs_num_noise      = src->bs_num_noise;
00765     dst->bs_frame_class    = src->bs_frame_class;
00766     dst->e_a[1]            = src->e_a[1];
00767 }
00768 
00770 static void read_sbr_dtdf(SpectralBandReplication *sbr, GetBitContext *gb,
00771                           SBRData *ch_data)
00772 {
00773     get_bits1_vector(gb, ch_data->bs_df_env,   ch_data->bs_num_env);
00774     get_bits1_vector(gb, ch_data->bs_df_noise, ch_data->bs_num_noise);
00775 }
00776 
00778 static void read_sbr_invf(SpectralBandReplication *sbr, GetBitContext *gb,
00779                           SBRData *ch_data)
00780 {
00781     int i;
00782 
00783     memcpy(ch_data->bs_invf_mode[1], ch_data->bs_invf_mode[0], 5 * sizeof(uint8_t));
00784     for (i = 0; i < sbr->n_q; i++)
00785         ch_data->bs_invf_mode[0][i] = get_bits(gb, 2);
00786 }
00787 
00788 static void read_sbr_envelope(SpectralBandReplication *sbr, GetBitContext *gb,
00789                               SBRData *ch_data, int ch)
00790 {
00791     int bits;
00792     int i, j, k;
00793     VLC_TYPE (*t_huff)[2], (*f_huff)[2];
00794     int t_lav, f_lav;
00795     const int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
00796     const int odd = sbr->n[1] & 1;
00797 
00798     if (sbr->bs_coupling && ch) {
00799         if (ch_data->bs_amp_res) {
00800             bits   = 5;
00801             t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_3_0DB].table;
00802             t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_3_0DB];
00803             f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
00804             f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
00805         } else {
00806             bits   = 6;
00807             t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_1_5DB].table;
00808             t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_1_5DB];
00809             f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_1_5DB].table;
00810             f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_1_5DB];
00811         }
00812     } else {
00813         if (ch_data->bs_amp_res) {
00814             bits   = 6;
00815             t_huff = vlc_sbr[T_HUFFMAN_ENV_3_0DB].table;
00816             t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_3_0DB];
00817             f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
00818             f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
00819         } else {
00820             bits   = 7;
00821             t_huff = vlc_sbr[T_HUFFMAN_ENV_1_5DB].table;
00822             t_lav  = vlc_sbr_lav[T_HUFFMAN_ENV_1_5DB];
00823             f_huff = vlc_sbr[F_HUFFMAN_ENV_1_5DB].table;
00824             f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_1_5DB];
00825         }
00826     }
00827 
00828     for (i = 0; i < ch_data->bs_num_env; i++) {
00829         if (ch_data->bs_df_env[i]) {
00830             // bs_freq_res[0] == bs_freq_res[bs_num_env] from prev frame
00831             if (ch_data->bs_freq_res[i + 1] == ch_data->bs_freq_res[i]) {
00832                 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
00833                     ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
00834             } else if (ch_data->bs_freq_res[i + 1]) {
00835                 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
00836                     k = (j + odd) >> 1; // find k such that f_tablelow[k] <= f_tablehigh[j] < f_tablelow[k + 1]
00837                     ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
00838                 }
00839             } else {
00840                 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
00841                     k = j ? 2*j - odd : 0; // find k such that f_tablehigh[k] == f_tablelow[j]
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             }
00845         } else {
00846             ch_data->env_facs[i + 1][0] = delta * get_bits(gb, bits); // bs_env_start_value_balance
00847             for (j = 1; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
00848                 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);
00849         }
00850     }
00851 
00852     //assign 0th elements of env_facs from last elements
00853     memcpy(ch_data->env_facs[0], ch_data->env_facs[ch_data->bs_num_env],
00854            sizeof(ch_data->env_facs[0]));
00855 }
00856 
00857 static void read_sbr_noise(SpectralBandReplication *sbr, GetBitContext *gb,
00858                            SBRData *ch_data, int ch)
00859 {
00860     int i, j;
00861     VLC_TYPE (*t_huff)[2], (*f_huff)[2];
00862     int t_lav, f_lav;
00863     int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
00864 
00865     if (sbr->bs_coupling && ch) {
00866         t_huff = vlc_sbr[T_HUFFMAN_NOISE_BAL_3_0DB].table;
00867         t_lav  = vlc_sbr_lav[T_HUFFMAN_NOISE_BAL_3_0DB];
00868         f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
00869         f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
00870     } else {
00871         t_huff = vlc_sbr[T_HUFFMAN_NOISE_3_0DB].table;
00872         t_lav  = vlc_sbr_lav[T_HUFFMAN_NOISE_3_0DB];
00873         f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
00874         f_lav  = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
00875     }
00876 
00877     for (i = 0; i < ch_data->bs_num_noise; i++) {
00878         if (ch_data->bs_df_noise[i]) {
00879             for (j = 0; j < sbr->n_q; j++)
00880                 ch_data->noise_facs[i + 1][j] = ch_data->noise_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 2) - t_lav);
00881         } else {
00882             ch_data->noise_facs[i + 1][0] = delta * get_bits(gb, 5); // bs_noise_start_value_balance or bs_noise_start_value_level
00883             for (j = 1; j < sbr->n_q; j++)
00884                 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);
00885         }
00886     }
00887 
00888     //assign 0th elements of noise_facs from last elements
00889     memcpy(ch_data->noise_facs[0], ch_data->noise_facs[ch_data->bs_num_noise],
00890            sizeof(ch_data->noise_facs[0]));
00891 }
00892 
00893 static void read_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
00894                                GetBitContext *gb,
00895                                int bs_extension_id, int *num_bits_left)
00896 {
00897     switch (bs_extension_id) {
00898     case EXTENSION_ID_PS:
00899         if (!ac->m4ac.ps) {
00900             av_log(ac->avctx, AV_LOG_ERROR, "Parametric Stereo signaled to be not-present but was found in the bitstream.\n");
00901             skip_bits_long(gb, *num_bits_left); // bs_fill_bits
00902             *num_bits_left = 0;
00903         } else {
00904 #if 1
00905             *num_bits_left -= ff_ps_read_data(ac->avctx, gb, &sbr->ps, *num_bits_left);
00906 #else
00907             av_log_missing_feature(ac->avctx, "Parametric Stereo is", 0);
00908             skip_bits_long(gb, *num_bits_left); // bs_fill_bits
00909             *num_bits_left = 0;
00910 #endif
00911         }
00912         break;
00913     default:
00914         av_log_missing_feature(ac->avctx, "Reserved SBR extensions are", 1);
00915         skip_bits_long(gb, *num_bits_left); // bs_fill_bits
00916         *num_bits_left = 0;
00917         break;
00918     }
00919 }
00920 
00921 static int read_sbr_single_channel_element(AACContext *ac,
00922                                             SpectralBandReplication *sbr,
00923                                             GetBitContext *gb)
00924 {
00925     if (get_bits1(gb)) // bs_data_extra
00926         skip_bits(gb, 4); // bs_reserved
00927 
00928     if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
00929         return -1;
00930     read_sbr_dtdf(sbr, gb, &sbr->data[0]);
00931     read_sbr_invf(sbr, gb, &sbr->data[0]);
00932     read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
00933     read_sbr_noise(sbr, gb, &sbr->data[0], 0);
00934 
00935     if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
00936         get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
00937 
00938     return 0;
00939 }
00940 
00941 static int read_sbr_channel_pair_element(AACContext *ac,
00942                                           SpectralBandReplication *sbr,
00943                                           GetBitContext *gb)
00944 {
00945     if (get_bits1(gb))    // bs_data_extra
00946         skip_bits(gb, 8); // bs_reserved
00947 
00948     if ((sbr->bs_coupling = get_bits1(gb))) {
00949         if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
00950             return -1;
00951         copy_sbr_grid(&sbr->data[1], &sbr->data[0]);
00952         read_sbr_dtdf(sbr, gb, &sbr->data[0]);
00953         read_sbr_dtdf(sbr, gb, &sbr->data[1]);
00954         read_sbr_invf(sbr, gb, &sbr->data[0]);
00955         memcpy(sbr->data[1].bs_invf_mode[1], sbr->data[1].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
00956         memcpy(sbr->data[1].bs_invf_mode[0], sbr->data[0].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
00957         read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
00958         read_sbr_noise(sbr, gb, &sbr->data[0], 0);
00959         read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
00960         read_sbr_noise(sbr, gb, &sbr->data[1], 1);
00961     } else {
00962         if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]) ||
00963             read_sbr_grid(ac, sbr, gb, &sbr->data[1]))
00964             return -1;
00965         read_sbr_dtdf(sbr, gb, &sbr->data[0]);
00966         read_sbr_dtdf(sbr, gb, &sbr->data[1]);
00967         read_sbr_invf(sbr, gb, &sbr->data[0]);
00968         read_sbr_invf(sbr, gb, &sbr->data[1]);
00969         read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
00970         read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
00971         read_sbr_noise(sbr, gb, &sbr->data[0], 0);
00972         read_sbr_noise(sbr, gb, &sbr->data[1], 1);
00973     }
00974 
00975     if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
00976         get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
00977     if ((sbr->data[1].bs_add_harmonic_flag = get_bits1(gb)))
00978         get_bits1_vector(gb, sbr->data[1].bs_add_harmonic, sbr->n[1]);
00979 
00980     return 0;
00981 }
00982 
00983 static unsigned int read_sbr_data(AACContext *ac, SpectralBandReplication *sbr,
00984                                   GetBitContext *gb, int id_aac)
00985 {
00986     unsigned int cnt = get_bits_count(gb);
00987 
00988     if (id_aac == TYPE_SCE || id_aac == TYPE_CCE) {
00989         if (read_sbr_single_channel_element(ac, sbr, gb)) {
00990             sbr->start = 0;
00991             return get_bits_count(gb) - cnt;
00992         }
00993     } else if (id_aac == TYPE_CPE) {
00994         if (read_sbr_channel_pair_element(ac, sbr, gb)) {
00995             sbr->start = 0;
00996             return get_bits_count(gb) - cnt;
00997         }
00998     } else {
00999         av_log(ac->avctx, AV_LOG_ERROR,
01000             "Invalid bitstream - cannot apply SBR to element type %d\n", id_aac);
01001         sbr->start = 0;
01002         return get_bits_count(gb) - cnt;
01003     }
01004     if (get_bits1(gb)) { // bs_extended_data
01005         int num_bits_left = get_bits(gb, 4); // bs_extension_size
01006         if (num_bits_left == 15)
01007             num_bits_left += get_bits(gb, 8); // bs_esc_count
01008 
01009         num_bits_left <<= 3;
01010         while (num_bits_left > 7) {
01011             num_bits_left -= 2;
01012             read_sbr_extension(ac, sbr, gb, get_bits(gb, 2), &num_bits_left); // bs_extension_id
01013         }
01014         if (num_bits_left < 0) {
01015             av_log(ac->avctx, AV_LOG_ERROR, "SBR Extension over read.\n");
01016         }
01017         if (num_bits_left > 0)
01018             skip_bits(gb, num_bits_left);
01019     }
01020 
01021     return get_bits_count(gb) - cnt;
01022 }
01023 
01024 static void sbr_reset(AACContext *ac, SpectralBandReplication *sbr)
01025 {
01026     int err;
01027     err = sbr_make_f_master(ac, sbr, &sbr->spectrum_params);
01028     if (err >= 0)
01029         err = sbr_make_f_derived(ac, sbr);
01030     if (err < 0) {
01031         av_log(ac->avctx, AV_LOG_ERROR,
01032                "SBR reset failed. Switching SBR to pure upsampling mode.\n");
01033         sbr->start = 0;
01034     }
01035 }
01036 
01045 int ff_decode_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
01046                             GetBitContext *gb_host, int crc, int cnt, int id_aac)
01047 {
01048     unsigned int num_sbr_bits = 0, num_align_bits;
01049     unsigned bytes_read;
01050     GetBitContext gbc = *gb_host, *gb = &gbc;
01051     skip_bits_long(gb_host, cnt*8 - 4);
01052 
01053     sbr->reset = 0;
01054 
01055     if (!sbr->sample_rate)
01056         sbr->sample_rate = 2 * ac->m4ac.sample_rate; //TODO use the nominal sample rate for arbitrary sample rate support
01057     if (!ac->m4ac.ext_sample_rate)
01058         ac->m4ac.ext_sample_rate = 2 * ac->m4ac.sample_rate;
01059 
01060     if (crc) {
01061         skip_bits(gb, 10); // bs_sbr_crc_bits; TODO - implement CRC check
01062         num_sbr_bits += 10;
01063     }
01064 
01065     //Save some state from the previous frame.
01066     sbr->kx[0] = sbr->kx[1];
01067     sbr->m[0] = sbr->m[1];
01068 
01069     num_sbr_bits++;
01070     if (get_bits1(gb)) // bs_header_flag
01071         num_sbr_bits += read_sbr_header(sbr, gb);
01072 
01073     if (sbr->reset)
01074         sbr_reset(ac, sbr);
01075 
01076     if (sbr->start)
01077         num_sbr_bits  += read_sbr_data(ac, sbr, gb, id_aac);
01078 
01079     num_align_bits = ((cnt << 3) - 4 - num_sbr_bits) & 7;
01080     bytes_read = ((num_sbr_bits + num_align_bits + 4) >> 3);
01081 
01082     if (bytes_read > cnt) {
01083         av_log(ac->avctx, AV_LOG_ERROR,
01084                "Expected to read %d SBR bytes actually read %d.\n", cnt, bytes_read);
01085     }
01086     return cnt;
01087 }
01088 
01090 static void sbr_dequant(SpectralBandReplication *sbr, int id_aac)
01091 {
01092     int k, e;
01093     int ch;
01094 
01095     if (id_aac == TYPE_CPE && sbr->bs_coupling) {
01096         float alpha      = sbr->data[0].bs_amp_res ?  1.0f :  0.5f;
01097         float pan_offset = sbr->data[0].bs_amp_res ? 12.0f : 24.0f;
01098         for (e = 1; e <= sbr->data[0].bs_num_env; e++) {
01099             for (k = 0; k < sbr->n[sbr->data[0].bs_freq_res[e]]; k++) {
01100                 float temp1 = exp2f(sbr->data[0].env_facs[e][k] * alpha + 7.0f);
01101                 float temp2 = exp2f((pan_offset - sbr->data[1].env_facs[e][k]) * alpha);
01102                 float fac   = temp1 / (1.0f + temp2);
01103                 sbr->data[0].env_facs[e][k] = fac;
01104                 sbr->data[1].env_facs[e][k] = fac * temp2;
01105             }
01106         }
01107         for (e = 1; e <= sbr->data[0].bs_num_noise; e++) {
01108             for (k = 0; k < sbr->n_q; k++) {
01109                 float temp1 = exp2f(NOISE_FLOOR_OFFSET - sbr->data[0].noise_facs[e][k] + 1);
01110                 float temp2 = exp2f(12 - sbr->data[1].noise_facs[e][k]);
01111                 float fac   = temp1 / (1.0f + temp2);
01112                 sbr->data[0].noise_facs[e][k] = fac;
01113                 sbr->data[1].noise_facs[e][k] = fac * temp2;
01114             }
01115         }
01116     } else { // SCE or one non-coupled CPE
01117         for (ch = 0; ch < (id_aac == TYPE_CPE) + 1; ch++) {
01118             float alpha = sbr->data[ch].bs_amp_res ? 1.0f : 0.5f;
01119             for (e = 1; e <= sbr->data[ch].bs_num_env; e++)
01120                 for (k = 0; k < sbr->n[sbr->data[ch].bs_freq_res[e]]; k++)
01121                     sbr->data[ch].env_facs[e][k] =
01122                         exp2f(alpha * sbr->data[ch].env_facs[e][k] + 6.0f);
01123             for (e = 1; e <= sbr->data[ch].bs_num_noise; e++)
01124                 for (k = 0; k < sbr->n_q; k++)
01125                     sbr->data[ch].noise_facs[e][k] =
01126                         exp2f(NOISE_FLOOR_OFFSET - sbr->data[ch].noise_facs[e][k]);
01127         }
01128     }
01129 }
01130 
01137 static void sbr_qmf_analysis(DSPContext *dsp, FFTContext *mdct, const float *in, float *x,
01138                              float z[320], float W[2][32][32][2],
01139                              float scale)
01140 {
01141     int i, k;
01142     memcpy(W[0], W[1], sizeof(W[0]));
01143     memcpy(x    , x+1024, (320-32)*sizeof(x[0]));
01144     if (scale != 1.0f)
01145         dsp->vector_fmul_scalar(x+288, in, scale, 1024);
01146     else
01147         memcpy(x+288, in, 1024*sizeof(*x));
01148     for (i = 0; i < 32; i++) { // numTimeSlots*RATE = 16*2 as 960 sample frames
01149                                // are not supported
01150         dsp->vector_fmul_reverse(z, sbr_qmf_window_ds, x, 320);
01151         for (k = 0; k < 64; k++) {
01152             float f = z[k] + z[k + 64] + z[k + 128] + z[k + 192] + z[k + 256];
01153             z[k] = f;
01154         }
01155         //Shuffle to IMDCT
01156         z[64] = z[0];
01157         for (k = 1; k < 32; k++) {
01158             z[64+2*k-1] =  z[   k];
01159             z[64+2*k  ] = -z[64-k];
01160         }
01161         z[64+63] = z[32];
01162 
01163         ff_imdct_half(mdct, z, z+64);
01164         for (k = 0; k < 32; k++) {
01165             W[1][i][k][0] = -z[63-k];
01166             W[1][i][k][1] = z[k];
01167         }
01168         x += 32;
01169     }
01170 }
01171 
01176 static void sbr_qmf_synthesis(DSPContext *dsp, FFTContext *mdct,
01177                               float *out, float X[2][38][64],
01178                               float mdct_buf[2][64],
01179                               float *v0, int *v_off, const unsigned int div,
01180                               float bias, float scale)
01181 {
01182     int i, n;
01183     const float *sbr_qmf_window = div ? sbr_qmf_window_ds : sbr_qmf_window_us;
01184     int scale_and_bias = scale != 1.0f || bias != 0.0f;
01185     const int step = 128 >> div;
01186     float *v;
01187     for (i = 0; i < 32; i++) {
01188         if (*v_off < step) {
01189             int saved_samples = (1280 - 128) >> div;
01190             memcpy(&v0[SBR_SYNTHESIS_BUF_SIZE - saved_samples], v0, saved_samples * sizeof(float));
01191             *v_off = SBR_SYNTHESIS_BUF_SIZE - saved_samples - step;
01192         } else {
01193             *v_off -= step;
01194         }
01195         v = v0 + *v_off;
01196         if (div) {
01197             for (n = 0; n < 32; n++) {
01198                 X[0][i][   n] = -X[0][i][n];
01199                 X[0][i][32+n] =  X[1][i][31-n];
01200             }
01201             ff_imdct_half(mdct, mdct_buf[0], X[0][i]);
01202             for (n = 0; n < 32; n++) {
01203                 v[     n] =  mdct_buf[0][63 - 2*n];
01204                 v[63 - n] = -mdct_buf[0][62 - 2*n];
01205             }
01206         } else {
01207             for (n = 1; n < 64; n+=2) {
01208                 X[1][i][n] = -X[1][i][n];
01209             }
01210             ff_imdct_half(mdct, mdct_buf[0], X[0][i]);
01211             ff_imdct_half(mdct, mdct_buf[1], X[1][i]);
01212             for (n = 0; n < 64; n++) {
01213                 v[      n] = -mdct_buf[0][63 -   n] + mdct_buf[1][  n    ];
01214                 v[127 - n] =  mdct_buf[0][63 -   n] + mdct_buf[1][  n    ];
01215             }
01216         }
01217         dsp->vector_fmul_add(out, v                , sbr_qmf_window               , zero64, 64 >> div);
01218         dsp->vector_fmul_add(out, v + ( 192 >> div), sbr_qmf_window + ( 64 >> div), out   , 64 >> div);
01219         dsp->vector_fmul_add(out, v + ( 256 >> div), sbr_qmf_window + (128 >> div), out   , 64 >> div);
01220         dsp->vector_fmul_add(out, v + ( 448 >> div), sbr_qmf_window + (192 >> div), out   , 64 >> div);
01221         dsp->vector_fmul_add(out, v + ( 512 >> div), sbr_qmf_window + (256 >> div), out   , 64 >> div);
01222         dsp->vector_fmul_add(out, v + ( 704 >> div), sbr_qmf_window + (320 >> div), out   , 64 >> div);
01223         dsp->vector_fmul_add(out, v + ( 768 >> div), sbr_qmf_window + (384 >> div), out   , 64 >> div);
01224         dsp->vector_fmul_add(out, v + ( 960 >> div), sbr_qmf_window + (448 >> div), out   , 64 >> div);
01225         dsp->vector_fmul_add(out, v + (1024 >> div), sbr_qmf_window + (512 >> div), out   , 64 >> div);
01226         dsp->vector_fmul_add(out, v + (1216 >> div), sbr_qmf_window + (576 >> div), out   , 64 >> div);
01227         if (scale_and_bias)
01228             for (n = 0; n < 64 >> div; n++)
01229                 out[n] = out[n] * scale + bias;
01230         out += 64 >> div;
01231     }
01232 }
01233 
01234 static void autocorrelate(const float x[40][2], float phi[3][2][2], int lag)
01235 {
01236     int i;
01237     float real_sum = 0.0f;
01238     float imag_sum = 0.0f;
01239     if (lag) {
01240         for (i = 1; i < 38; i++) {
01241             real_sum += x[i][0] * x[i+lag][0] + x[i][1] * x[i+lag][1];
01242             imag_sum += x[i][0] * x[i+lag][1] - x[i][1] * x[i+lag][0];
01243         }
01244         phi[2-lag][1][0] = real_sum + x[ 0][0] * x[lag][0] + x[ 0][1] * x[lag][1];
01245         phi[2-lag][1][1] = imag_sum + x[ 0][0] * x[lag][1] - x[ 0][1] * x[lag][0];
01246         if (lag == 1) {
01247             phi[0][0][0] = real_sum + x[38][0] * x[39][0] + x[38][1] * x[39][1];
01248             phi[0][0][1] = imag_sum + x[38][0] * x[39][1] - x[38][1] * x[39][0];
01249         }
01250     } else {
01251         for (i = 1; i < 38; i++) {
01252             real_sum += x[i][0] * x[i][0] + x[i][1] * x[i][1];
01253         }
01254         phi[2][1][0] = real_sum + x[ 0][0] * x[ 0][0] + x[ 0][1] * x[ 0][1];
01255         phi[1][0][0] = real_sum + x[38][0] * x[38][0] + x[38][1] * x[38][1];
01256     }
01257 }
01258 
01263 static void sbr_hf_inverse_filter(float (*alpha0)[2], float (*alpha1)[2],
01264                                   const float X_low[32][40][2], int k0)
01265 {
01266     int k;
01267     for (k = 0; k < k0; k++) {
01268         float phi[3][2][2], dk;
01269 
01270         autocorrelate(X_low[k], phi, 0);
01271         autocorrelate(X_low[k], phi, 1);
01272         autocorrelate(X_low[k], phi, 2);
01273 
01274         dk =  phi[2][1][0] * phi[1][0][0] -
01275              (phi[1][1][0] * phi[1][1][0] + phi[1][1][1] * phi[1][1][1]) / 1.000001f;
01276 
01277         if (!dk) {
01278             alpha1[k][0] = 0;
01279             alpha1[k][1] = 0;
01280         } else {
01281             float temp_real, temp_im;
01282             temp_real = phi[0][0][0] * phi[1][1][0] -
01283                         phi[0][0][1] * phi[1][1][1] -
01284                         phi[0][1][0] * phi[1][0][0];
01285             temp_im   = phi[0][0][0] * phi[1][1][1] +
01286                         phi[0][0][1] * phi[1][1][0] -
01287                         phi[0][1][1] * phi[1][0][0];
01288 
01289             alpha1[k][0] = temp_real / dk;
01290             alpha1[k][1] = temp_im   / dk;
01291         }
01292 
01293         if (!phi[1][0][0]) {
01294             alpha0[k][0] = 0;
01295             alpha0[k][1] = 0;
01296         } else {
01297             float temp_real, temp_im;
01298             temp_real = phi[0][0][0] + alpha1[k][0] * phi[1][1][0] +
01299                                        alpha1[k][1] * phi[1][1][1];
01300             temp_im   = phi[0][0][1] + alpha1[k][1] * phi[1][1][0] -
01301                                        alpha1[k][0] * phi[1][1][1];
01302 
01303             alpha0[k][0] = -temp_real / phi[1][0][0];
01304             alpha0[k][1] = -temp_im   / phi[1][0][0];
01305         }
01306 
01307         if (alpha1[k][0] * alpha1[k][0] + alpha1[k][1] * alpha1[k][1] >= 16.0f ||
01308            alpha0[k][0] * alpha0[k][0] + alpha0[k][1] * alpha0[k][1] >= 16.0f) {
01309             alpha1[k][0] = 0;
01310             alpha1[k][1] = 0;
01311             alpha0[k][0] = 0;
01312             alpha0[k][1] = 0;
01313         }
01314     }
01315 }
01316 
01318 static void sbr_chirp(SpectralBandReplication *sbr, SBRData *ch_data)
01319 {
01320     int i;
01321     float new_bw;
01322     static const float bw_tab[] = { 0.0f, 0.75f, 0.9f, 0.98f };
01323 
01324     for (i = 0; i < sbr->n_q; i++) {
01325         if (ch_data->bs_invf_mode[0][i] + ch_data->bs_invf_mode[1][i] == 1) {
01326             new_bw = 0.6f;
01327         } else
01328             new_bw = bw_tab[ch_data->bs_invf_mode[0][i]];
01329 
01330         if (new_bw < ch_data->bw_array[i]) {
01331             new_bw = 0.75f    * new_bw + 0.25f    * ch_data->bw_array[i];
01332         } else
01333             new_bw = 0.90625f * new_bw + 0.09375f * ch_data->bw_array[i];
01334         ch_data->bw_array[i] = new_bw < 0.015625f ? 0.0f : new_bw;
01335     }
01336 }
01337 
01339 static int sbr_lf_gen(AACContext *ac, SpectralBandReplication *sbr,
01340                       float X_low[32][40][2], const float W[2][32][32][2])
01341 {
01342     int i, k;
01343     const int t_HFGen = 8;
01344     const int i_f = 32;
01345     memset(X_low, 0, 32*sizeof(*X_low));
01346     for (k = 0; k < sbr->kx[1]; k++) {
01347         for (i = t_HFGen; i < i_f + t_HFGen; i++) {
01348             X_low[k][i][0] = W[1][i - t_HFGen][k][0];
01349             X_low[k][i][1] = W[1][i - t_HFGen][k][1];
01350         }
01351     }
01352     for (k = 0; k < sbr->kx[0]; k++) {
01353         for (i = 0; i < t_HFGen; i++) {
01354             X_low[k][i][0] = W[0][i + i_f - t_HFGen][k][0];
01355             X_low[k][i][1] = W[0][i + i_f - t_HFGen][k][1];
01356         }
01357     }
01358     return 0;
01359 }
01360 
01362 static int sbr_hf_gen(AACContext *ac, SpectralBandReplication *sbr,
01363                       float X_high[64][40][2], const float X_low[32][40][2],
01364                       const float (*alpha0)[2], const float (*alpha1)[2],
01365                       const float bw_array[5], const uint8_t *t_env,
01366                       int bs_num_env)
01367 {
01368     int i, j, x;
01369     int g = 0;
01370     int k = sbr->kx[1];
01371     for (j = 0; j < sbr->num_patches; j++) {
01372         for (x = 0; x < sbr->patch_num_subbands[j]; x++, k++) {
01373             float alpha[4];
01374             const int p = sbr->patch_start_subband[j] + x;
01375             while (g <= sbr->n_q && k >= sbr->f_tablenoise[g])
01376                 g++;
01377             g--;
01378 
01379             if (g < 0) {
01380                 av_log(ac->avctx, AV_LOG_ERROR,
01381                        "ERROR : no subband found for frequency %d\n", k);
01382                 return -1;
01383             }
01384 
01385             alpha[0] = alpha1[p][0] * bw_array[g] * bw_array[g];
01386             alpha[1] = alpha1[p][1] * bw_array[g] * bw_array[g];
01387             alpha[2] = alpha0[p][0] * bw_array[g];
01388             alpha[3] = alpha0[p][1] * bw_array[g];
01389 
01390             for (i = 2 * t_env[0]; i < 2 * t_env[bs_num_env]; i++) {
01391                 const int idx = i + ENVELOPE_ADJUSTMENT_OFFSET;
01392                 X_high[k][idx][0] =
01393                     X_low[p][idx - 2][0] * alpha[0] -
01394                     X_low[p][idx - 2][1] * alpha[1] +
01395                     X_low[p][idx - 1][0] * alpha[2] -
01396                     X_low[p][idx - 1][1] * alpha[3] +
01397                     X_low[p][idx][0];
01398                 X_high[k][idx][1] =
01399                     X_low[p][idx - 2][1] * alpha[0] +
01400                     X_low[p][idx - 2][0] * alpha[1] +
01401                     X_low[p][idx - 1][1] * alpha[2] +
01402                     X_low[p][idx - 1][0] * alpha[3] +
01403                     X_low[p][idx][1];
01404             }
01405         }
01406     }
01407     if (k < sbr->m[1] + sbr->kx[1])
01408         memset(X_high + k, 0, (sbr->m[1] + sbr->kx[1] - k) * sizeof(*X_high));
01409 
01410     return 0;
01411 }
01412 
01414 static int sbr_x_gen(SpectralBandReplication *sbr, float X[2][38][64],
01415                      const float X_low[32][40][2], const float Y[2][38][64][2],
01416                      int ch)
01417 {
01418     int k, i;
01419     const int i_f = 32;
01420     const int i_Temp = FFMAX(2*sbr->data[ch].t_env_num_env_old - i_f, 0);
01421     memset(X, 0, 2*sizeof(*X));
01422     for (k = 0; k < sbr->kx[0]; k++) {
01423         for (i = 0; i < i_Temp; i++) {
01424             X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
01425             X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
01426         }
01427     }
01428     for (; k < sbr->kx[0] + sbr->m[0]; k++) {
01429         for (i = 0; i < i_Temp; i++) {
01430             X[0][i][k] = Y[0][i + i_f][k][0];
01431             X[1][i][k] = Y[0][i + i_f][k][1];
01432         }
01433     }
01434 
01435     for (k = 0; k < sbr->kx[1]; k++) {
01436         for (i = i_Temp; i < 38; i++) {
01437             X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
01438             X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
01439         }
01440     }
01441     for (; k < sbr->kx[1] + sbr->m[1]; k++) {
01442         for (i = i_Temp; i < i_f; i++) {
01443             X[0][i][k] = Y[1][i][k][0];
01444             X[1][i][k] = Y[1][i][k][1];
01445         }
01446     }
01447     return 0;
01448 }
01449 
01453 static void sbr_mapping(AACContext *ac, SpectralBandReplication *sbr,
01454                         SBRData *ch_data, int e_a[2])
01455 {
01456     int e, i, m;
01457 
01458     memset(ch_data->s_indexmapped[1], 0, 7*sizeof(ch_data->s_indexmapped[1]));
01459     for (e = 0; e < ch_data->bs_num_env; e++) {
01460         const unsigned int ilim = sbr->n[ch_data->bs_freq_res[e + 1]];
01461         uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
01462         int k;
01463 
01464         for (i = 0; i < ilim; i++)
01465             for (m = table[i]; m < table[i + 1]; m++)
01466                 sbr->e_origmapped[e][m - sbr->kx[1]] = ch_data->env_facs[e+1][i];
01467 
01468         // ch_data->bs_num_noise > 1 => 2 noise floors
01469         k = (ch_data->bs_num_noise > 1) && (ch_data->t_env[e] >= ch_data->t_q[1]);
01470         for (i = 0; i < sbr->n_q; i++)
01471             for (m = sbr->f_tablenoise[i]; m < sbr->f_tablenoise[i + 1]; m++)
01472                 sbr->q_mapped[e][m - sbr->kx[1]] = ch_data->noise_facs[k+1][i];
01473 
01474         for (i = 0; i < sbr->n[1]; i++) {
01475             if (ch_data->bs_add_harmonic_flag) {
01476                 const unsigned int m_midpoint =
01477                     (sbr->f_tablehigh[i] + sbr->f_tablehigh[i + 1]) >> 1;
01478 
01479                 ch_data->s_indexmapped[e + 1][m_midpoint - sbr->kx[1]] = ch_data->bs_add_harmonic[i] *
01480                     (e >= e_a[1] || (ch_data->s_indexmapped[0][m_midpoint - sbr->kx[1]] == 1));
01481             }
01482         }
01483 
01484         for (i = 0; i < ilim; i++) {
01485             int additional_sinusoid_present = 0;
01486             for (m = table[i]; m < table[i + 1]; m++) {
01487                 if (ch_data->s_indexmapped[e + 1][m - sbr->kx[1]]) {
01488                     additional_sinusoid_present = 1;
01489                     break;
01490                 }
01491             }
01492             memset(&sbr->s_mapped[e][table[i] - sbr->kx[1]], additional_sinusoid_present,
01493                    (table[i + 1] - table[i]) * sizeof(sbr->s_mapped[e][0]));
01494         }
01495     }
01496 
01497     memcpy(ch_data->s_indexmapped[0], ch_data->s_indexmapped[ch_data->bs_num_env], sizeof(ch_data->s_indexmapped[0]));
01498 }
01499 
01501 static void sbr_env_estimate(float (*e_curr)[48], float X_high[64][40][2],
01502                              SpectralBandReplication *sbr, SBRData *ch_data)
01503 {
01504     int e, i, m;
01505 
01506     if (sbr->bs_interpol_freq) {
01507         for (e = 0; e < ch_data->bs_num_env; e++) {
01508             const float recip_env_size = 0.5f / (ch_data->t_env[e + 1] - ch_data->t_env[e]);
01509             int ilb = ch_data->t_env[e]     * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
01510             int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
01511 
01512             for (m = 0; m < sbr->m[1]; m++) {
01513                 float sum = 0.0f;
01514 
01515                 for (i = ilb; i < iub; i++) {
01516                     sum += X_high[m + sbr->kx[1]][i][0] * X_high[m + sbr->kx[1]][i][0] +
01517                            X_high[m + sbr->kx[1]][i][1] * X_high[m + sbr->kx[1]][i][1];
01518                 }
01519                 e_curr[e][m] = sum * recip_env_size;
01520             }
01521         }
01522     } else {
01523         int k, p;
01524 
01525         for (e = 0; e < ch_data->bs_num_env; e++) {
01526             const int env_size = 2 * (ch_data->t_env[e + 1] - ch_data->t_env[e]);
01527             int ilb = ch_data->t_env[e]     * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
01528             int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
01529             const uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
01530 
01531             for (p = 0; p < sbr->n[ch_data->bs_freq_res[e + 1]]; p++) {
01532                 float sum = 0.0f;
01533                 const int den = env_size * (table[p + 1] - table[p]);
01534 
01535                 for (k = table[p]; k < table[p + 1]; k++) {
01536                     for (i = ilb; i < iub; i++) {
01537                         sum += X_high[k][i][0] * X_high[k][i][0] +
01538                                X_high[k][i][1] * X_high[k][i][1];
01539                     }
01540                 }
01541                 sum /= den;
01542                 for (k = table[p]; k < table[p + 1]; k++) {
01543                     e_curr[e][k - sbr->kx[1]] = sum;
01544                 }
01545             }
01546         }
01547     }
01548 }
01549 
01554 static void sbr_gain_calc(AACContext *ac, SpectralBandReplication *sbr,
01555                           SBRData *ch_data, const int e_a[2])
01556 {
01557     int e, k, m;
01558     // max gain limits : -3dB, 0dB, 3dB, inf dB (limiter off)
01559     static const float limgain[4] = { 0.70795, 1.0, 1.41254, 10000000000 };
01560 
01561     for (e = 0; e < ch_data->bs_num_env; e++) {
01562         int delta = !((e == e_a[1]) || (e == e_a[0]));
01563         for (k = 0; k < sbr->n_lim; k++) {
01564             float gain_boost, gain_max;
01565             float sum[2] = { 0.0f, 0.0f };
01566             for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
01567                 const float temp = sbr->e_origmapped[e][m] / (1.0f + sbr->q_mapped[e][m]);
01568                 sbr->q_m[e][m] = sqrtf(temp * sbr->q_mapped[e][m]);
01569                 sbr->s_m[e][m] = sqrtf(temp * ch_data->s_indexmapped[e + 1][m]);
01570                 if (!sbr->s_mapped[e][m]) {
01571                     sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] /
01572                                             ((1.0f + sbr->e_curr[e][m]) *
01573                                              (1.0f + sbr->q_mapped[e][m] * delta)));
01574                 } else {
01575                     sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] * sbr->q_mapped[e][m] /
01576                                             ((1.0f + sbr->e_curr[e][m]) *
01577                                              (1.0f + sbr->q_mapped[e][m])));
01578                 }
01579             }
01580             for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
01581                 sum[0] += sbr->e_origmapped[e][m];
01582                 sum[1] += sbr->e_curr[e][m];
01583             }
01584             gain_max = limgain[sbr->bs_limiter_gains] * sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
01585             gain_max = FFMIN(100000, gain_max);
01586             for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
01587                 float q_m_max   = sbr->q_m[e][m] * gain_max / sbr->gain[e][m];
01588                 sbr->q_m[e][m]  = FFMIN(sbr->q_m[e][m], q_m_max);
01589                 sbr->gain[e][m] = FFMIN(sbr->gain[e][m], gain_max);
01590             }
01591             sum[0] = sum[1] = 0.0f;
01592             for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
01593                 sum[0] += sbr->e_origmapped[e][m];
01594                 sum[1] += sbr->e_curr[e][m] * sbr->gain[e][m] * sbr->gain[e][m]
01595                           + sbr->s_m[e][m] * sbr->s_m[e][m]
01596                           + (delta && !sbr->s_m[e][m]) * sbr->q_m[e][m] * sbr->q_m[e][m];
01597             }
01598             gain_boost = sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
01599             gain_boost = FFMIN(1.584893192, gain_boost);
01600             for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
01601                 sbr->gain[e][m] *= gain_boost;
01602                 sbr->q_m[e][m]  *= gain_boost;
01603                 sbr->s_m[e][m]  *= gain_boost;
01604             }
01605         }
01606     }
01607 }
01608 
01610 static void sbr_hf_assemble(float Y[2][38][64][2], const float X_high[64][40][2],
01611                             SpectralBandReplication *sbr, SBRData *ch_data,
01612                             const int e_a[2])
01613 {
01614     int e, i, j, m;
01615     const int h_SL = 4 * !sbr->bs_smoothing_mode;
01616     const int kx = sbr->kx[1];
01617     const int m_max = sbr->m[1];
01618     static const float h_smooth[5] = {
01619         0.33333333333333,
01620         0.30150283239582,
01621         0.21816949906249,
01622         0.11516383427084,
01623         0.03183050093751,
01624     };
01625     static const int8_t phi[2][4] = {
01626         {  1,  0, -1,  0}, // real
01627         {  0,  1,  0, -1}, // imaginary
01628     };
01629     float (*g_temp)[48] = ch_data->g_temp, (*q_temp)[48] = ch_data->q_temp;
01630     int indexnoise = ch_data->f_indexnoise;
01631     int indexsine  = ch_data->f_indexsine;
01632     memcpy(Y[0], Y[1], sizeof(Y[0]));
01633 
01634     if (sbr->reset) {
01635         for (i = 0; i < h_SL; i++) {
01636             memcpy(g_temp[i + 2*ch_data->t_env[0]], sbr->gain[0], m_max * sizeof(sbr->gain[0][0]));
01637             memcpy(q_temp[i + 2*ch_data->t_env[0]], sbr->q_m[0],  m_max * sizeof(sbr->q_m[0][0]));
01638         }
01639     } else if (h_SL) {
01640         memcpy(g_temp[2*ch_data->t_env[0]], g_temp[2*ch_data->t_env_num_env_old], 4*sizeof(g_temp[0]));
01641         memcpy(q_temp[2*ch_data->t_env[0]], q_temp[2*ch_data->t_env_num_env_old], 4*sizeof(q_temp[0]));
01642     }
01643 
01644     for (e = 0; e < ch_data->bs_num_env; e++) {
01645         for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
01646             memcpy(g_temp[h_SL + i], sbr->gain[e], m_max * sizeof(sbr->gain[0][0]));
01647             memcpy(q_temp[h_SL + i], sbr->q_m[e],  m_max * sizeof(sbr->q_m[0][0]));
01648         }
01649     }
01650 
01651     for (e = 0; e < ch_data->bs_num_env; e++) {
01652         for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
01653             int phi_sign = (1 - 2*(kx & 1));
01654 
01655             if (h_SL && e != e_a[0] && e != e_a[1]) {
01656                 for (m = 0; m < m_max; m++) {
01657                     const int idx1 = i + h_SL;
01658                     float g_filt = 0.0f;
01659                     for (j = 0; j <= h_SL; j++)
01660                         g_filt += g_temp[idx1 - j][m] * h_smooth[j];
01661                     Y[1][i][m + kx][0] =
01662                         X_high[m + kx][i + ENVELOPE_ADJUSTMENT_OFFSET][0] * g_filt;
01663                     Y[1][i][m + kx][1] =
01664                         X_high[m + kx][i + ENVELOPE_ADJUSTMENT_OFFSET][1] * g_filt;
01665                 }
01666             } else {
01667                 for (m = 0; m < m_max; m++) {
01668                     const float g_filt = g_temp[i + h_SL][m];
01669                     Y[1][i][m + kx][0] =
01670                         X_high[m + kx][i + ENVELOPE_ADJUSTMENT_OFFSET][0] * g_filt;
01671                     Y[1][i][m + kx][1] =
01672                         X_high[m + kx][i + ENVELOPE_ADJUSTMENT_OFFSET][1] * g_filt;
01673                 }
01674             }
01675 
01676             if (e != e_a[0] && e != e_a[1]) {
01677                 for (m = 0; m < m_max; m++) {
01678                     indexnoise = (indexnoise + 1) & 0x1ff;
01679                     if (sbr->s_m[e][m]) {
01680                         Y[1][i][m + kx][0] +=
01681                             sbr->s_m[e][m] * phi[0][indexsine];
01682                         Y[1][i][m + kx][1] +=
01683                             sbr->s_m[e][m] * (phi[1][indexsine] * phi_sign);
01684                     } else {
01685                         float q_filt;
01686                         if (h_SL) {
01687                             const int idx1 = i + h_SL;
01688                             q_filt = 0.0f;
01689                             for (j = 0; j <= h_SL; j++)
01690                                 q_filt += q_temp[idx1 - j][m] * h_smooth[j];
01691                         } else {
01692                             q_filt = q_temp[i][m];
01693                         }
01694                         Y[1][i][m + kx][0] +=
01695                             q_filt * sbr_noise_table[indexnoise][0];
01696                         Y[1][i][m + kx][1] +=
01697                             q_filt * sbr_noise_table[indexnoise][1];
01698                     }
01699                     phi_sign = -phi_sign;
01700                 }
01701             } else {
01702                 indexnoise = (indexnoise + m_max) & 0x1ff;
01703                 for (m = 0; m < m_max; m++) {
01704                     Y[1][i][m + kx][0] +=
01705                         sbr->s_m[e][m] * phi[0][indexsine];
01706                     Y[1][i][m + kx][1] +=
01707                         sbr->s_m[e][m] * (phi[1][indexsine] * phi_sign);
01708                     phi_sign = -phi_sign;
01709                 }
01710             }
01711             indexsine = (indexsine + 1) & 3;
01712         }
01713     }
01714     ch_data->f_indexnoise = indexnoise;
01715     ch_data->f_indexsine  = indexsine;
01716 }
01717 
01718 void ff_sbr_apply(AACContext *ac, SpectralBandReplication *sbr, int id_aac,
01719                   float* L, float* R)
01720 {
01721     int downsampled = ac->m4ac.ext_sample_rate < sbr->sample_rate;
01722     int ch;
01723     int nch = (id_aac == TYPE_CPE) ? 2 : 1;
01724 
01725     if (sbr->start) {
01726         sbr_dequant(sbr, id_aac);
01727     }
01728     for (ch = 0; ch < nch; ch++) {
01729         /* decode channel */
01730         sbr_qmf_analysis(&ac->dsp, &sbr->mdct_ana, ch ? R : L, sbr->data[ch].analysis_filterbank_samples,
01731                          (float*)sbr->qmf_filter_scratch,
01732                          sbr->data[ch].W, 1/(-1024 * ac->sf_scale));
01733         sbr_lf_gen(ac, sbr, sbr->X_low, sbr->data[ch].W);
01734         if (sbr->start) {
01735             sbr_hf_inverse_filter(sbr->alpha0, sbr->alpha1, sbr->X_low, sbr->k[0]);
01736             sbr_chirp(sbr, &sbr->data[ch]);
01737             sbr_hf_gen(ac, sbr, sbr->X_high, sbr->X_low, sbr->alpha0, sbr->alpha1,
01738                        sbr->data[ch].bw_array, sbr->data[ch].t_env,
01739                        sbr->data[ch].bs_num_env);
01740 
01741             // hf_adj
01742             sbr_mapping(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
01743             sbr_env_estimate(sbr->e_curr, sbr->X_high, sbr, &sbr->data[ch]);
01744             sbr_gain_calc(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
01745             sbr_hf_assemble(sbr->data[ch].Y, sbr->X_high, sbr, &sbr->data[ch],
01746                             sbr->data[ch].e_a);
01747         }
01748 
01749         /* synthesis */
01750         sbr_x_gen(sbr, sbr->X[ch], sbr->X_low, sbr->data[ch].Y, ch);
01751     }
01752 
01753     if (ac->m4ac.ps == 1) {
01754         if (sbr->ps.start) {
01755             ff_ps_apply(ac->avctx, &sbr->ps, sbr->X[0], sbr->X[1], sbr->kx[1] + sbr->m[1]);
01756         } else {
01757             memcpy(sbr->X[1], sbr->X[0], sizeof(sbr->X[0]));
01758         }
01759         nch = 2;
01760     }
01761 
01762     sbr_qmf_synthesis(&ac->dsp, &sbr->mdct, L, sbr->X[0], sbr->qmf_filter_scratch,
01763                       sbr->data[0].synthesis_filterbank_samples,
01764                       &sbr->data[0].synthesis_filterbank_samples_offset,
01765                       downsampled,
01766                       ac->add_bias, -1024 * ac->sf_scale);
01767     if (nch == 2)
01768         sbr_qmf_synthesis(&ac->dsp, &sbr->mdct, R, sbr->X[1], sbr->qmf_filter_scratch,
01769                           sbr->data[1].synthesis_filterbank_samples,
01770                           &sbr->data[1].synthesis_filterbank_samples_offset,
01771                           downsampled,
01772                           ac->add_bias, -1024 * ac->sf_scale);
01773 }