blob: 15956e3f052662640ece04ad16a8194f6fa11ae7
| 1 | /* |
| 2 | * AAC Spectral Band Replication decoding functions |
| 3 | * Copyright (c) 2008-2009 Robert Swain ( rob opendot cl ) |
| 4 | * Copyright (c) 2009-2010 Alex Converse <alex.converse@gmail.com> |
| 5 | * |
| 6 | * This file is part of FFmpeg. |
| 7 | * |
| 8 | * FFmpeg is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU Lesser General Public |
| 10 | * License as published by the Free Software Foundation; either |
| 11 | * version 2.1 of the License, or (at your option) any later version. |
| 12 | * |
| 13 | * FFmpeg is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 | * Lesser General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU Lesser General Public |
| 19 | * License along with FFmpeg; if not, write to the Free Software |
| 20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 21 | */ |
| 22 | |
| 23 | /** |
| 24 | * @file |
| 25 | * AAC Spectral Band Replication decoding functions |
| 26 | * @author Robert Swain ( rob opendot cl ) |
| 27 | */ |
| 28 | #define USE_FIXED 0 |
| 29 | |
| 30 | #include "aac.h" |
| 31 | #include "sbr.h" |
| 32 | #include "aacsbr.h" |
| 33 | #include "aacsbrdata.h" |
| 34 | #include "aacsbr_tablegen.h" |
| 35 | #include "fft.h" |
| 36 | #include "internal.h" |
| 37 | #include "aacps.h" |
| 38 | #include "sbrdsp.h" |
| 39 | #include "libavutil/internal.h" |
| 40 | #include "libavutil/libm.h" |
| 41 | #include "libavutil/avassert.h" |
| 42 | |
| 43 | #include <stdint.h> |
| 44 | #include <float.h> |
| 45 | #include <math.h> |
| 46 | |
| 47 | #if ARCH_MIPS |
| 48 | #include "mips/aacsbr_mips.h" |
| 49 | #endif /* ARCH_MIPS */ |
| 50 | |
| 51 | static VLC vlc_sbr[10]; |
| 52 | static void aacsbr_func_ptr_init(AACSBRContext *c); |
| 53 | |
| 54 | static void make_bands(int16_t* bands, int start, int stop, int num_bands) |
| 55 | { |
| 56 | int k, previous, present; |
| 57 | float base, prod; |
| 58 | |
| 59 | base = powf((float)stop / start, 1.0f / num_bands); |
| 60 | prod = start; |
| 61 | previous = start; |
| 62 | |
| 63 | for (k = 0; k < num_bands-1; k++) { |
| 64 | prod *= base; |
| 65 | present = lrintf(prod); |
| 66 | bands[k] = present - previous; |
| 67 | previous = present; |
| 68 | } |
| 69 | bands[num_bands-1] = stop - previous; |
| 70 | } |
| 71 | |
| 72 | /// Dequantization and stereo decoding (14496-3 sp04 p203) |
| 73 | static void sbr_dequant(SpectralBandReplication *sbr, int id_aac) |
| 74 | { |
| 75 | int k, e; |
| 76 | int ch; |
| 77 | static const double exp2_tab[2] = {1, M_SQRT2}; |
| 78 | if (id_aac == TYPE_CPE && sbr->bs_coupling) { |
| 79 | int pan_offset = sbr->data[0].bs_amp_res ? 12 : 24; |
| 80 | for (e = 1; e <= sbr->data[0].bs_num_env; e++) { |
| 81 | for (k = 0; k < sbr->n[sbr->data[0].bs_freq_res[e]]; k++) { |
| 82 | float temp1, temp2, fac; |
| 83 | if (sbr->data[0].bs_amp_res) { |
| 84 | temp1 = ff_exp2fi(sbr->data[0].env_facs_q[e][k] + 7); |
| 85 | temp2 = ff_exp2fi(pan_offset - sbr->data[1].env_facs_q[e][k]); |
| 86 | } |
| 87 | else { |
| 88 | temp1 = ff_exp2fi((sbr->data[0].env_facs_q[e][k]>>1) + 7) * |
| 89 | exp2_tab[sbr->data[0].env_facs_q[e][k] & 1]; |
| 90 | temp2 = ff_exp2fi((pan_offset - sbr->data[1].env_facs_q[e][k])>>1) * |
| 91 | exp2_tab[(pan_offset - sbr->data[1].env_facs_q[e][k]) & 1]; |
| 92 | } |
| 93 | if (temp1 > 1E20) { |
| 94 | av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n"); |
| 95 | temp1 = 1; |
| 96 | } |
| 97 | fac = temp1 / (1.0f + temp2); |
| 98 | sbr->data[0].env_facs[e][k] = fac; |
| 99 | sbr->data[1].env_facs[e][k] = fac * temp2; |
| 100 | } |
| 101 | } |
| 102 | for (e = 1; e <= sbr->data[0].bs_num_noise; e++) { |
| 103 | for (k = 0; k < sbr->n_q; k++) { |
| 104 | float temp1 = ff_exp2fi(NOISE_FLOOR_OFFSET - sbr->data[0].noise_facs_q[e][k] + 1); |
| 105 | float temp2 = ff_exp2fi(12 - sbr->data[1].noise_facs_q[e][k]); |
| 106 | float fac; |
| 107 | av_assert0(temp1 <= 1E20); |
| 108 | fac = temp1 / (1.0f + temp2); |
| 109 | sbr->data[0].noise_facs[e][k] = fac; |
| 110 | sbr->data[1].noise_facs[e][k] = fac * temp2; |
| 111 | } |
| 112 | } |
| 113 | } else { // SCE or one non-coupled CPE |
| 114 | for (ch = 0; ch < (id_aac == TYPE_CPE) + 1; ch++) { |
| 115 | for (e = 1; e <= sbr->data[ch].bs_num_env; e++) |
| 116 | for (k = 0; k < sbr->n[sbr->data[ch].bs_freq_res[e]]; k++){ |
| 117 | if (sbr->data[ch].bs_amp_res) |
| 118 | sbr->data[ch].env_facs[e][k] = ff_exp2fi(sbr->data[ch].env_facs_q[e][k] + 6); |
| 119 | else |
| 120 | sbr->data[ch].env_facs[e][k] = ff_exp2fi((sbr->data[ch].env_facs_q[e][k]>>1) + 6) |
| 121 | * exp2_tab[sbr->data[ch].env_facs_q[e][k] & 1]; |
| 122 | if (sbr->data[ch].env_facs[e][k] > 1E20) { |
| 123 | av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n"); |
| 124 | sbr->data[ch].env_facs[e][k] = 1; |
| 125 | } |
| 126 | } |
| 127 | |
| 128 | for (e = 1; e <= sbr->data[ch].bs_num_noise; e++) |
| 129 | for (k = 0; k < sbr->n_q; k++) |
| 130 | sbr->data[ch].noise_facs[e][k] = |
| 131 | ff_exp2fi(NOISE_FLOOR_OFFSET - sbr->data[ch].noise_facs_q[e][k]); |
| 132 | } |
| 133 | } |
| 134 | } |
| 135 | |
| 136 | /** High Frequency Generation (14496-3 sp04 p214+) and Inverse Filtering |
| 137 | * (14496-3 sp04 p214) |
| 138 | * Warning: This routine does not seem numerically stable. |
| 139 | */ |
| 140 | static void sbr_hf_inverse_filter(SBRDSPContext *dsp, |
| 141 | float (*alpha0)[2], float (*alpha1)[2], |
| 142 | const float X_low[32][40][2], int k0) |
| 143 | { |
| 144 | int k; |
| 145 | for (k = 0; k < k0; k++) { |
| 146 | LOCAL_ALIGNED_16(float, phi, [3], [2][2]); |
| 147 | float dk; |
| 148 | |
| 149 | dsp->autocorrelate(X_low[k], phi); |
| 150 | |
| 151 | dk = phi[2][1][0] * phi[1][0][0] - |
| 152 | (phi[1][1][0] * phi[1][1][0] + phi[1][1][1] * phi[1][1][1]) / 1.000001f; |
| 153 | |
| 154 | if (!dk) { |
| 155 | alpha1[k][0] = 0; |
| 156 | alpha1[k][1] = 0; |
| 157 | } else { |
| 158 | float temp_real, temp_im; |
| 159 | temp_real = phi[0][0][0] * phi[1][1][0] - |
| 160 | phi[0][0][1] * phi[1][1][1] - |
| 161 | phi[0][1][0] * phi[1][0][0]; |
| 162 | temp_im = phi[0][0][0] * phi[1][1][1] + |
| 163 | phi[0][0][1] * phi[1][1][0] - |
| 164 | phi[0][1][1] * phi[1][0][0]; |
| 165 | |
| 166 | alpha1[k][0] = temp_real / dk; |
| 167 | alpha1[k][1] = temp_im / dk; |
| 168 | } |
| 169 | |
| 170 | if (!phi[1][0][0]) { |
| 171 | alpha0[k][0] = 0; |
| 172 | alpha0[k][1] = 0; |
| 173 | } else { |
| 174 | float temp_real, temp_im; |
| 175 | temp_real = phi[0][0][0] + alpha1[k][0] * phi[1][1][0] + |
| 176 | alpha1[k][1] * phi[1][1][1]; |
| 177 | temp_im = phi[0][0][1] + alpha1[k][1] * phi[1][1][0] - |
| 178 | alpha1[k][0] * phi[1][1][1]; |
| 179 | |
| 180 | alpha0[k][0] = -temp_real / phi[1][0][0]; |
| 181 | alpha0[k][1] = -temp_im / phi[1][0][0]; |
| 182 | } |
| 183 | |
| 184 | if (alpha1[k][0] * alpha1[k][0] + alpha1[k][1] * alpha1[k][1] >= 16.0f || |
| 185 | alpha0[k][0] * alpha0[k][0] + alpha0[k][1] * alpha0[k][1] >= 16.0f) { |
| 186 | alpha1[k][0] = 0; |
| 187 | alpha1[k][1] = 0; |
| 188 | alpha0[k][0] = 0; |
| 189 | alpha0[k][1] = 0; |
| 190 | } |
| 191 | } |
| 192 | } |
| 193 | |
| 194 | /// Chirp Factors (14496-3 sp04 p214) |
| 195 | static void sbr_chirp(SpectralBandReplication *sbr, SBRData *ch_data) |
| 196 | { |
| 197 | int i; |
| 198 | float new_bw; |
| 199 | static const float bw_tab[] = { 0.0f, 0.75f, 0.9f, 0.98f }; |
| 200 | |
| 201 | for (i = 0; i < sbr->n_q; i++) { |
| 202 | if (ch_data->bs_invf_mode[0][i] + ch_data->bs_invf_mode[1][i] == 1) { |
| 203 | new_bw = 0.6f; |
| 204 | } else |
| 205 | new_bw = bw_tab[ch_data->bs_invf_mode[0][i]]; |
| 206 | |
| 207 | if (new_bw < ch_data->bw_array[i]) { |
| 208 | new_bw = 0.75f * new_bw + 0.25f * ch_data->bw_array[i]; |
| 209 | } else |
| 210 | new_bw = 0.90625f * new_bw + 0.09375f * ch_data->bw_array[i]; |
| 211 | ch_data->bw_array[i] = new_bw < 0.015625f ? 0.0f : new_bw; |
| 212 | } |
| 213 | } |
| 214 | |
| 215 | /** |
| 216 | * Calculation of levels of additional HF signal components (14496-3 sp04 p219) |
| 217 | * and Calculation of gain (14496-3 sp04 p219) |
| 218 | */ |
| 219 | static void sbr_gain_calc(AACContext *ac, SpectralBandReplication *sbr, |
| 220 | SBRData *ch_data, const int e_a[2]) |
| 221 | { |
| 222 | int e, k, m; |
| 223 | // max gain limits : -3dB, 0dB, 3dB, inf dB (limiter off) |
| 224 | static const float limgain[4] = { 0.70795, 1.0, 1.41254, 10000000000 }; |
| 225 | |
| 226 | for (e = 0; e < ch_data->bs_num_env; e++) { |
| 227 | int delta = !((e == e_a[1]) || (e == e_a[0])); |
| 228 | for (k = 0; k < sbr->n_lim; k++) { |
| 229 | float gain_boost, gain_max; |
| 230 | float sum[2] = { 0.0f, 0.0f }; |
| 231 | for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) { |
| 232 | const float temp = sbr->e_origmapped[e][m] / (1.0f + sbr->q_mapped[e][m]); |
| 233 | sbr->q_m[e][m] = sqrtf(temp * sbr->q_mapped[e][m]); |
| 234 | sbr->s_m[e][m] = sqrtf(temp * ch_data->s_indexmapped[e + 1][m]); |
| 235 | if (!sbr->s_mapped[e][m]) { |
| 236 | sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] / |
| 237 | ((1.0f + sbr->e_curr[e][m]) * |
| 238 | (1.0f + sbr->q_mapped[e][m] * delta))); |
| 239 | } else { |
| 240 | sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] * sbr->q_mapped[e][m] / |
| 241 | ((1.0f + sbr->e_curr[e][m]) * |
| 242 | (1.0f + sbr->q_mapped[e][m]))); |
| 243 | } |
| 244 | } |
| 245 | for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) { |
| 246 | sum[0] += sbr->e_origmapped[e][m]; |
| 247 | sum[1] += sbr->e_curr[e][m]; |
| 248 | } |
| 249 | gain_max = limgain[sbr->bs_limiter_gains] * sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1])); |
| 250 | gain_max = FFMIN(100000.f, gain_max); |
| 251 | for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) { |
| 252 | float q_m_max = sbr->q_m[e][m] * gain_max / sbr->gain[e][m]; |
| 253 | sbr->q_m[e][m] = FFMIN(sbr->q_m[e][m], q_m_max); |
| 254 | sbr->gain[e][m] = FFMIN(sbr->gain[e][m], gain_max); |
| 255 | } |
| 256 | sum[0] = sum[1] = 0.0f; |
| 257 | for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) { |
| 258 | sum[0] += sbr->e_origmapped[e][m]; |
| 259 | sum[1] += sbr->e_curr[e][m] * sbr->gain[e][m] * sbr->gain[e][m] |
| 260 | + sbr->s_m[e][m] * sbr->s_m[e][m] |
| 261 | + (delta && !sbr->s_m[e][m]) * sbr->q_m[e][m] * sbr->q_m[e][m]; |
| 262 | } |
| 263 | gain_boost = sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1])); |
| 264 | gain_boost = FFMIN(1.584893192f, gain_boost); |
| 265 | for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) { |
| 266 | sbr->gain[e][m] *= gain_boost; |
| 267 | sbr->q_m[e][m] *= gain_boost; |
| 268 | sbr->s_m[e][m] *= gain_boost; |
| 269 | } |
| 270 | } |
| 271 | } |
| 272 | } |
| 273 | |
| 274 | /// Assembling HF Signals (14496-3 sp04 p220) |
| 275 | static void sbr_hf_assemble(float Y1[38][64][2], |
| 276 | const float X_high[64][40][2], |
| 277 | SpectralBandReplication *sbr, SBRData *ch_data, |
| 278 | const int e_a[2]) |
| 279 | { |
| 280 | int e, i, j, m; |
| 281 | const int h_SL = 4 * !sbr->bs_smoothing_mode; |
| 282 | const int kx = sbr->kx[1]; |
| 283 | const int m_max = sbr->m[1]; |
| 284 | static const float h_smooth[5] = { |
| 285 | 0.33333333333333, |
| 286 | 0.30150283239582, |
| 287 | 0.21816949906249, |
| 288 | 0.11516383427084, |
| 289 | 0.03183050093751, |
| 290 | }; |
| 291 | float (*g_temp)[48] = ch_data->g_temp, (*q_temp)[48] = ch_data->q_temp; |
| 292 | int indexnoise = ch_data->f_indexnoise; |
| 293 | int indexsine = ch_data->f_indexsine; |
| 294 | |
| 295 | if (sbr->reset) { |
| 296 | for (i = 0; i < h_SL; i++) { |
| 297 | memcpy(g_temp[i + 2*ch_data->t_env[0]], sbr->gain[0], m_max * sizeof(sbr->gain[0][0])); |
| 298 | memcpy(q_temp[i + 2*ch_data->t_env[0]], sbr->q_m[0], m_max * sizeof(sbr->q_m[0][0])); |
| 299 | } |
| 300 | } else if (h_SL) { |
| 301 | for (i = 0; i < 4; i++) { |
| 302 | memcpy(g_temp[i + 2 * ch_data->t_env[0]], |
| 303 | g_temp[i + 2 * ch_data->t_env_num_env_old], |
| 304 | sizeof(g_temp[0])); |
| 305 | memcpy(q_temp[i + 2 * ch_data->t_env[0]], |
| 306 | q_temp[i + 2 * ch_data->t_env_num_env_old], |
| 307 | sizeof(q_temp[0])); |
| 308 | } |
| 309 | } |
| 310 | |
| 311 | for (e = 0; e < ch_data->bs_num_env; e++) { |
| 312 | for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) { |
| 313 | memcpy(g_temp[h_SL + i], sbr->gain[e], m_max * sizeof(sbr->gain[0][0])); |
| 314 | memcpy(q_temp[h_SL + i], sbr->q_m[e], m_max * sizeof(sbr->q_m[0][0])); |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | for (e = 0; e < ch_data->bs_num_env; e++) { |
| 319 | for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) { |
| 320 | LOCAL_ALIGNED_16(float, g_filt_tab, [48]); |
| 321 | LOCAL_ALIGNED_16(float, q_filt_tab, [48]); |
| 322 | float *g_filt, *q_filt; |
| 323 | |
| 324 | if (h_SL && e != e_a[0] && e != e_a[1]) { |
| 325 | g_filt = g_filt_tab; |
| 326 | q_filt = q_filt_tab; |
| 327 | for (m = 0; m < m_max; m++) { |
| 328 | const int idx1 = i + h_SL; |
| 329 | g_filt[m] = 0.0f; |
| 330 | q_filt[m] = 0.0f; |
| 331 | for (j = 0; j <= h_SL; j++) { |
| 332 | g_filt[m] += g_temp[idx1 - j][m] * h_smooth[j]; |
| 333 | q_filt[m] += q_temp[idx1 - j][m] * h_smooth[j]; |
| 334 | } |
| 335 | } |
| 336 | } else { |
| 337 | g_filt = g_temp[i + h_SL]; |
| 338 | q_filt = q_temp[i]; |
| 339 | } |
| 340 | |
| 341 | sbr->dsp.hf_g_filt(Y1[i] + kx, X_high + kx, g_filt, m_max, |
| 342 | i + ENVELOPE_ADJUSTMENT_OFFSET); |
| 343 | |
| 344 | if (e != e_a[0] && e != e_a[1]) { |
| 345 | sbr->dsp.hf_apply_noise[indexsine](Y1[i] + kx, sbr->s_m[e], |
| 346 | q_filt, indexnoise, |
| 347 | kx, m_max); |
| 348 | } else { |
| 349 | int idx = indexsine&1; |
| 350 | int A = (1-((indexsine+(kx & 1))&2)); |
| 351 | int B = (A^(-idx)) + idx; |
| 352 | float *out = &Y1[i][kx][idx]; |
| 353 | float *in = sbr->s_m[e]; |
| 354 | for (m = 0; m+1 < m_max; m+=2) { |
| 355 | out[2*m ] += in[m ] * A; |
| 356 | out[2*m+2] += in[m+1] * B; |
| 357 | } |
| 358 | if(m_max&1) |
| 359 | out[2*m ] += in[m ] * A; |
| 360 | } |
| 361 | indexnoise = (indexnoise + m_max) & 0x1ff; |
| 362 | indexsine = (indexsine + 1) & 3; |
| 363 | } |
| 364 | } |
| 365 | ch_data->f_indexnoise = indexnoise; |
| 366 | ch_data->f_indexsine = indexsine; |
| 367 | } |
| 368 | |
| 369 | #include "aacsbr_template.c" |
| 370 |