1/* 2 * TwinVQ decoder 3 * Copyright (c) 2009 Vitor Sessak 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22#include <math.h> 23#include <stdint.h> 24 25#include "libavutil/channel_layout.h" 26#include "libavutil/float_dsp.h" 27#include "avcodec.h" 28#include "fft.h" 29#include "internal.h" 30#include "lsp.h" 31#include "sinewin.h" 32#include "twinvq.h" 33 34/** 35 * Evaluate a single LPC amplitude spectrum envelope coefficient from the line 36 * spectrum pairs. 37 * 38 * @param lsp a vector of the cosine of the LSP values 39 * @param cos_val cos(PI*i/N) where i is the index of the LPC amplitude 40 * @param order the order of the LSP (and the size of the *lsp buffer). Must 41 * be a multiple of four. 42 * @return the LPC value 43 * 44 * @todo reuse code from Vorbis decoder: vorbis_floor0_decode 45 */ 46static float eval_lpc_spectrum(const float *lsp, float cos_val, int order) 47{ 48 int j; 49 float p = 0.5f; 50 float q = 0.5f; 51 float two_cos_w = 2.0f * cos_val; 52 53 for (j = 0; j + 1 < order; j += 2 * 2) { 54 // Unroll the loop once since order is a multiple of four 55 q *= lsp[j] - two_cos_w; 56 p *= lsp[j + 1] - two_cos_w; 57 58 q *= lsp[j + 2] - two_cos_w; 59 p *= lsp[j + 3] - two_cos_w; 60 } 61 62 p *= p * (2.0f - two_cos_w); 63 q *= q * (2.0f + two_cos_w); 64 65 return 0.5 / (p + q); 66} 67 68/** 69 * Evaluate the LPC amplitude spectrum envelope from the line spectrum pairs. 70 */ 71static void eval_lpcenv(TwinVQContext *tctx, const float *cos_vals, float *lpc) 72{ 73 int i; 74 const TwinVQModeTab *mtab = tctx->mtab; 75 int size_s = mtab->size / mtab->fmode[TWINVQ_FT_SHORT].sub; 76 77 for (i = 0; i < size_s / 2; i++) { 78 float cos_i = tctx->cos_tabs[0][i]; 79 lpc[i] = eval_lpc_spectrum(cos_vals, cos_i, mtab->n_lsp); 80 lpc[size_s - i - 1] = eval_lpc_spectrum(cos_vals, -cos_i, mtab->n_lsp); 81 } 82} 83 84static void interpolate(float *out, float v1, float v2, int size) 85{ 86 int i; 87 float step = (v1 - v2) / (size + 1); 88 89 for (i = 0; i < size; i++) { 90 v2 += step; 91 out[i] = v2; 92 } 93} 94 95static inline float get_cos(int idx, int part, const float *cos_tab, int size) 96{ 97 return part ? -cos_tab[size - idx - 1] 98 : cos_tab[idx]; 99} 100 101/** 102 * Evaluate the LPC amplitude spectrum envelope from the line spectrum pairs. 103 * Probably for speed reasons, the coefficients are evaluated as 104 * siiiibiiiisiiiibiiiisiiiibiiiisiiiibiiiis ... 105 * where s is an evaluated value, i is a value interpolated from the others 106 * and b might be either calculated or interpolated, depending on an 107 * unexplained condition. 108 * 109 * @param step the size of a block "siiiibiiii" 110 * @param in the cosine of the LSP data 111 * @param part is 0 for 0...PI (positive cosine values) and 1 for PI...2PI 112 * (negative cosine values) 113 * @param size the size of the whole output 114 */ 115static inline void eval_lpcenv_or_interp(TwinVQContext *tctx, 116 enum TwinVQFrameType ftype, 117 float *out, const float *in, 118 int size, int step, int part) 119{ 120 int i; 121 const TwinVQModeTab *mtab = tctx->mtab; 122 const float *cos_tab = tctx->cos_tabs[ftype]; 123 124 // Fill the 's' 125 for (i = 0; i < size; i += step) 126 out[i] = 127 eval_lpc_spectrum(in, 128 get_cos(i, part, cos_tab, size), 129 mtab->n_lsp); 130 131 // Fill the 'iiiibiiii' 132 for (i = step; i <= size - 2 * step; i += step) { 133 if (out[i + step] + out[i - step] > 1.95 * out[i] || 134 out[i + step] >= out[i - step]) { 135 interpolate(out + i - step + 1, out[i], out[i - step], step - 1); 136 } else { 137 out[i - step / 2] = 138 eval_lpc_spectrum(in, 139 get_cos(i - step / 2, part, cos_tab, size), 140 mtab->n_lsp); 141 interpolate(out + i - step + 1, out[i - step / 2], 142 out[i - step], step / 2 - 1); 143 interpolate(out + i - step / 2 + 1, out[i], 144 out[i - step / 2], step / 2 - 1); 145 } 146 } 147 148 interpolate(out + size - 2 * step + 1, out[size - step], 149 out[size - 2 * step], step - 1); 150} 151 152static void eval_lpcenv_2parts(TwinVQContext *tctx, enum TwinVQFrameType ftype, 153 const float *buf, float *lpc, 154 int size, int step) 155{ 156 eval_lpcenv_or_interp(tctx, ftype, lpc, buf, size / 2, step, 0); 157 eval_lpcenv_or_interp(tctx, ftype, lpc + size / 2, buf, size / 2, 158 2 * step, 1); 159 160 interpolate(lpc + size / 2 - step + 1, lpc[size / 2], 161 lpc[size / 2 - step], step); 162 163 twinvq_memset_float(lpc + size - 2 * step + 1, lpc[size - 2 * step], 164 2 * step - 1); 165} 166 167/** 168 * Inverse quantization. Read CB coefficients for cb1 and cb2 from the 169 * bitstream, sum the corresponding vectors and write the result to *out 170 * after permutation. 171 */ 172static void dequant(TwinVQContext *tctx, const uint8_t *cb_bits, float *out, 173 enum TwinVQFrameType ftype, 174 const int16_t *cb0, const int16_t *cb1, int cb_len) 175{ 176 int pos = 0; 177 int i, j; 178 179 for (i = 0; i < tctx->n_div[ftype]; i++) { 180 int tmp0, tmp1; 181 int sign0 = 1; 182 int sign1 = 1; 183 const int16_t *tab0, *tab1; 184 int length = tctx->length[ftype][i >= tctx->length_change[ftype]]; 185 int bitstream_second_part = (i >= tctx->bits_main_spec_change[ftype]); 186 187 int bits = tctx->bits_main_spec[0][ftype][bitstream_second_part]; 188 tmp0 = *cb_bits++; 189 if (bits == 7) { 190 if (tmp0 & 0x40) 191 sign0 = -1; 192 tmp0 &= 0x3F; 193 } 194 195 bits = tctx->bits_main_spec[1][ftype][bitstream_second_part]; 196 tmp1 = *cb_bits++; 197 if (bits == 7) { 198 if (tmp1 & 0x40) 199 sign1 = -1; 200 tmp1 &= 0x3F; 201 } 202 203 tab0 = cb0 + tmp0 * cb_len; 204 tab1 = cb1 + tmp1 * cb_len; 205 206 for (j = 0; j < length; j++) 207 out[tctx->permut[ftype][pos + j]] = sign0 * tab0[j] + 208 sign1 * tab1[j]; 209 210 pos += length; 211 } 212} 213 214static void dec_gain(TwinVQContext *tctx, 215 enum TwinVQFrameType ftype, float *out) 216{ 217 const TwinVQModeTab *mtab = tctx->mtab; 218 const TwinVQFrameData *bits = &tctx->bits[tctx->cur_frame]; 219 int i, j; 220 int sub = mtab->fmode[ftype].sub; 221 float step = TWINVQ_AMP_MAX / ((1 << TWINVQ_GAIN_BITS) - 1); 222 float sub_step = TWINVQ_SUB_AMP_MAX / ((1 << TWINVQ_SUB_GAIN_BITS) - 1); 223 224 if (ftype == TWINVQ_FT_LONG) { 225 for (i = 0; i < tctx->avctx->channels; i++) 226 out[i] = (1.0 / (1 << 13)) * 227 twinvq_mulawinv(step * 0.5 + step * bits->gain_bits[i], 228 TWINVQ_AMP_MAX, TWINVQ_MULAW_MU); 229 } else { 230 for (i = 0; i < tctx->avctx->channels; i++) { 231 float val = (1.0 / (1 << 23)) * 232 twinvq_mulawinv(step * 0.5 + step * bits->gain_bits[i], 233 TWINVQ_AMP_MAX, TWINVQ_MULAW_MU); 234 235 for (j = 0; j < sub; j++) 236 out[i * sub + j] = 237 val * twinvq_mulawinv(sub_step * 0.5 + 238 sub_step * bits->sub_gain_bits[i * sub + j], 239 TWINVQ_SUB_AMP_MAX, TWINVQ_MULAW_MU); 240 } 241 } 242} 243 244/** 245 * Rearrange the LSP coefficients so that they have a minimum distance of 246 * min_dist. This function does it exactly as described in section of 3.2.4 247 * of the G.729 specification (but interestingly is different from what the 248 * reference decoder actually does). 249 */ 250static void rearrange_lsp(int order, float *lsp, float min_dist) 251{ 252 int i; 253 float min_dist2 = min_dist * 0.5; 254 for (i = 1; i < order; i++) 255 if (lsp[i] - lsp[i - 1] < min_dist) { 256 float avg = (lsp[i] + lsp[i - 1]) * 0.5; 257 258 lsp[i - 1] = avg - min_dist2; 259 lsp[i] = avg + min_dist2; 260 } 261} 262 263static void decode_lsp(TwinVQContext *tctx, int lpc_idx1, uint8_t *lpc_idx2, 264 int lpc_hist_idx, float *lsp, float *hist) 265{ 266 const TwinVQModeTab *mtab = tctx->mtab; 267 int i, j; 268 269 const float *cb = mtab->lspcodebook; 270 const float *cb2 = cb + (1 << mtab->lsp_bit1) * mtab->n_lsp; 271 const float *cb3 = cb2 + (1 << mtab->lsp_bit2) * mtab->n_lsp; 272 273 const int8_t funny_rounding[4] = { 274 -2, 275 mtab->lsp_split == 4 ? -2 : 1, 276 mtab->lsp_split == 4 ? -2 : 1, 277 0 278 }; 279 280 j = 0; 281 for (i = 0; i < mtab->lsp_split; i++) { 282 int chunk_end = ((i + 1) * mtab->n_lsp + funny_rounding[i]) / 283 mtab->lsp_split; 284 for (; j < chunk_end; j++) 285 lsp[j] = cb[lpc_idx1 * mtab->n_lsp + j] + 286 cb2[lpc_idx2[i] * mtab->n_lsp + j]; 287 } 288 289 rearrange_lsp(mtab->n_lsp, lsp, 0.0001); 290 291 for (i = 0; i < mtab->n_lsp; i++) { 292 float tmp1 = 1.0 - cb3[lpc_hist_idx * mtab->n_lsp + i]; 293 float tmp2 = hist[i] * cb3[lpc_hist_idx * mtab->n_lsp + i]; 294 hist[i] = lsp[i]; 295 lsp[i] = lsp[i] * tmp1 + tmp2; 296 } 297 298 rearrange_lsp(mtab->n_lsp, lsp, 0.0001); 299 rearrange_lsp(mtab->n_lsp, lsp, 0.000095); 300 ff_sort_nearly_sorted_floats(lsp, mtab->n_lsp); 301} 302 303static void dec_lpc_spectrum_inv(TwinVQContext *tctx, float *lsp, 304 enum TwinVQFrameType ftype, float *lpc) 305{ 306 int i; 307 int size = tctx->mtab->size / tctx->mtab->fmode[ftype].sub; 308 309 for (i = 0; i < tctx->mtab->n_lsp; i++) 310 lsp[i] = 2 * cos(lsp[i]); 311 312 switch (ftype) { 313 case TWINVQ_FT_LONG: 314 eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 8); 315 break; 316 case TWINVQ_FT_MEDIUM: 317 eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 2); 318 break; 319 case TWINVQ_FT_SHORT: 320 eval_lpcenv(tctx, lsp, lpc); 321 break; 322 } 323} 324 325static const uint8_t wtype_to_wsize[] = { 0, 0, 2, 2, 2, 1, 0, 1, 1 }; 326 327static void imdct_and_window(TwinVQContext *tctx, enum TwinVQFrameType ftype, 328 int wtype, float *in, float *prev, int ch) 329{ 330 FFTContext *mdct = &tctx->mdct_ctx[ftype]; 331 const TwinVQModeTab *mtab = tctx->mtab; 332 int bsize = mtab->size / mtab->fmode[ftype].sub; 333 int size = mtab->size; 334 float *buf1 = tctx->tmp_buf; 335 int j, first_wsize, wsize; // Window size 336 float *out = tctx->curr_frame + 2 * ch * mtab->size; 337 float *out2 = out; 338 float *prev_buf; 339 int types_sizes[] = { 340 mtab->size / mtab->fmode[TWINVQ_FT_LONG].sub, 341 mtab->size / mtab->fmode[TWINVQ_FT_MEDIUM].sub, 342 mtab->size / (mtab->fmode[TWINVQ_FT_SHORT].sub * 2), 343 }; 344 345 wsize = types_sizes[wtype_to_wsize[wtype]]; 346 first_wsize = wsize; 347 prev_buf = prev + (size - bsize) / 2; 348 349 for (j = 0; j < mtab->fmode[ftype].sub; j++) { 350 int sub_wtype = ftype == TWINVQ_FT_MEDIUM ? 8 : wtype; 351 352 if (!j && wtype == 4) 353 sub_wtype = 4; 354 else if (j == mtab->fmode[ftype].sub - 1 && wtype == 7) 355 sub_wtype = 7; 356 357 wsize = types_sizes[wtype_to_wsize[sub_wtype]]; 358 359 mdct->imdct_half(mdct, buf1 + bsize * j, in + bsize * j); 360 361 tctx->fdsp.vector_fmul_window(out2, prev_buf + (bsize - wsize) / 2, 362 buf1 + bsize * j, 363 ff_sine_windows[av_log2(wsize)], 364 wsize / 2); 365 out2 += wsize; 366 367 memcpy(out2, buf1 + bsize * j + wsize / 2, 368 (bsize - wsize / 2) * sizeof(float)); 369 370 out2 += ftype == TWINVQ_FT_MEDIUM ? (bsize - wsize) / 2 : bsize - wsize; 371 372 prev_buf = buf1 + bsize * j + bsize / 2; 373 } 374 375 tctx->last_block_pos[ch] = (size + first_wsize) / 2; 376} 377 378static void imdct_output(TwinVQContext *tctx, enum TwinVQFrameType ftype, 379 int wtype, float **out, int offset) 380{ 381 const TwinVQModeTab *mtab = tctx->mtab; 382 float *prev_buf = tctx->prev_frame + tctx->last_block_pos[0]; 383 int size1, size2, i; 384 float *out1, *out2; 385 386 for (i = 0; i < tctx->avctx->channels; i++) 387 imdct_and_window(tctx, ftype, wtype, 388 tctx->spectrum + i * mtab->size, 389 prev_buf + 2 * i * mtab->size, 390 i); 391 392 if (!out) 393 return; 394 395 size2 = tctx->last_block_pos[0]; 396 size1 = mtab->size - size2; 397 398 out1 = &out[0][0] + offset; 399 memcpy(out1, prev_buf, size1 * sizeof(*out1)); 400 memcpy(out1 + size1, tctx->curr_frame, size2 * sizeof(*out1)); 401 402 if (tctx->avctx->channels == 2) { 403 out2 = &out[1][0] + offset; 404 memcpy(out2, &prev_buf[2 * mtab->size], 405 size1 * sizeof(*out2)); 406 memcpy(out2 + size1, &tctx->curr_frame[2 * mtab->size], 407 size2 * sizeof(*out2)); 408 tctx->fdsp.butterflies_float(out1, out2, mtab->size); 409 } 410} 411 412static void read_and_decode_spectrum(TwinVQContext *tctx, float *out, 413 enum TwinVQFrameType ftype) 414{ 415 const TwinVQModeTab *mtab = tctx->mtab; 416 TwinVQFrameData *bits = &tctx->bits[tctx->cur_frame]; 417 int channels = tctx->avctx->channels; 418 int sub = mtab->fmode[ftype].sub; 419 int block_size = mtab->size / sub; 420 float gain[TWINVQ_CHANNELS_MAX * TWINVQ_SUBBLOCKS_MAX]; 421 float ppc_shape[TWINVQ_PPC_SHAPE_LEN_MAX * TWINVQ_CHANNELS_MAX * 4]; 422 423 int i, j; 424 425 dequant(tctx, bits->main_coeffs, out, ftype, 426 mtab->fmode[ftype].cb0, mtab->fmode[ftype].cb1, 427 mtab->fmode[ftype].cb_len_read); 428 429 dec_gain(tctx, ftype, gain); 430 431 if (ftype == TWINVQ_FT_LONG) { 432 int cb_len_p = (tctx->n_div[3] + mtab->ppc_shape_len * channels - 1) / 433 tctx->n_div[3]; 434 dequant(tctx, bits->ppc_coeffs, ppc_shape, 435 TWINVQ_FT_PPC, mtab->ppc_shape_cb, 436 mtab->ppc_shape_cb + cb_len_p * TWINVQ_PPC_SHAPE_CB_SIZE, 437 cb_len_p); 438 } 439 440 for (i = 0; i < channels; i++) { 441 float *chunk = out + mtab->size * i; 442 float lsp[TWINVQ_LSP_COEFS_MAX]; 443 444 for (j = 0; j < sub; j++) { 445 tctx->dec_bark_env(tctx, bits->bark1[i][j], 446 bits->bark_use_hist[i][j], i, 447 tctx->tmp_buf, gain[sub * i + j], ftype); 448 449 tctx->fdsp.vector_fmul(chunk + block_size * j, 450 chunk + block_size * j, 451 tctx->tmp_buf, block_size); 452 } 453 454 if (ftype == TWINVQ_FT_LONG) 455 tctx->decode_ppc(tctx, bits->p_coef[i], bits->g_coef[i], 456 ppc_shape + i * mtab->ppc_shape_len, chunk); 457 458 decode_lsp(tctx, bits->lpc_idx1[i], bits->lpc_idx2[i], 459 bits->lpc_hist_idx[i], lsp, tctx->lsp_hist[i]); 460 461 dec_lpc_spectrum_inv(tctx, lsp, ftype, tctx->tmp_buf); 462 463 for (j = 0; j < mtab->fmode[ftype].sub; j++) { 464 tctx->fdsp.vector_fmul(chunk, chunk, tctx->tmp_buf, block_size); 465 chunk += block_size; 466 } 467 } 468} 469 470const enum TwinVQFrameType ff_twinvq_wtype_to_ftype_table[] = { 471 TWINVQ_FT_LONG, TWINVQ_FT_LONG, TWINVQ_FT_SHORT, TWINVQ_FT_LONG, 472 TWINVQ_FT_MEDIUM, TWINVQ_FT_LONG, TWINVQ_FT_LONG, TWINVQ_FT_MEDIUM, 473 TWINVQ_FT_MEDIUM 474}; 475 476int ff_twinvq_decode_frame(AVCodecContext *avctx, void *data, 477 int *got_frame_ptr, AVPacket *avpkt) 478{ 479 AVFrame *frame = data; 480 const uint8_t *buf = avpkt->data; 481 int buf_size = avpkt->size; 482 TwinVQContext *tctx = avctx->priv_data; 483 const TwinVQModeTab *mtab = tctx->mtab; 484 float **out = NULL; 485 int ret; 486 487 /* get output buffer */ 488 if (tctx->discarded_packets >= 2) { 489 frame->nb_samples = mtab->size * tctx->frames_per_packet; 490 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) 491 return ret; 492 out = (float **)frame->extended_data; 493 } 494 495 if (buf_size < avctx->block_align) { 496 av_log(avctx, AV_LOG_ERROR, 497 "Frame too small (%d bytes). Truncated file?\n", buf_size); 498 return AVERROR(EINVAL); 499 } 500 501 if ((ret = tctx->read_bitstream(avctx, tctx, buf, buf_size)) < 0) 502 return ret; 503 504 for (tctx->cur_frame = 0; tctx->cur_frame < tctx->frames_per_packet; 505 tctx->cur_frame++) { 506 read_and_decode_spectrum(tctx, tctx->spectrum, 507 tctx->bits[tctx->cur_frame].ftype); 508 509 imdct_output(tctx, tctx->bits[tctx->cur_frame].ftype, 510 tctx->bits[tctx->cur_frame].window_type, out, 511 tctx->cur_frame * mtab->size); 512 513 FFSWAP(float *, tctx->curr_frame, tctx->prev_frame); 514 } 515 516 if (tctx->discarded_packets < 2) { 517 tctx->discarded_packets++; 518 *got_frame_ptr = 0; 519 return buf_size; 520 } 521 522 *got_frame_ptr = 1; 523 524 // VQF can deliver packets 1 byte greater than block align 525 if (buf_size == avctx->block_align + 1) 526 return buf_size; 527 return avctx->block_align; 528} 529 530/** 531 * Init IMDCT and windowing tables 532 */ 533static av_cold int init_mdct_win(TwinVQContext *tctx) 534{ 535 int i, j, ret; 536 const TwinVQModeTab *mtab = tctx->mtab; 537 int size_s = mtab->size / mtab->fmode[TWINVQ_FT_SHORT].sub; 538 int size_m = mtab->size / mtab->fmode[TWINVQ_FT_MEDIUM].sub; 539 int channels = tctx->avctx->channels; 540 float norm = channels == 1 ? 2.0 : 1.0; 541 542 for (i = 0; i < 3; i++) { 543 int bsize = tctx->mtab->size / tctx->mtab->fmode[i].sub; 544 if ((ret = ff_mdct_init(&tctx->mdct_ctx[i], av_log2(bsize) + 1, 1, 545 -sqrt(norm / bsize) / (1 << 15)))) 546 return ret; 547 } 548 549 FF_ALLOC_OR_GOTO(tctx->avctx, tctx->tmp_buf, 550 mtab->size * sizeof(*tctx->tmp_buf), alloc_fail); 551 552 FF_ALLOC_OR_GOTO(tctx->avctx, tctx->spectrum, 553 2 * mtab->size * channels * sizeof(*tctx->spectrum), 554 alloc_fail); 555 FF_ALLOC_OR_GOTO(tctx->avctx, tctx->curr_frame, 556 2 * mtab->size * channels * sizeof(*tctx->curr_frame), 557 alloc_fail); 558 FF_ALLOC_OR_GOTO(tctx->avctx, tctx->prev_frame, 559 2 * mtab->size * channels * sizeof(*tctx->prev_frame), 560 alloc_fail); 561 562 for (i = 0; i < 3; i++) { 563 int m = 4 * mtab->size / mtab->fmode[i].sub; 564 double freq = 2 * M_PI / m; 565 FF_ALLOC_OR_GOTO(tctx->avctx, tctx->cos_tabs[i], 566 (m / 4) * sizeof(*tctx->cos_tabs[i]), alloc_fail); 567 568 for (j = 0; j <= m / 8; j++) 569 tctx->cos_tabs[i][j] = cos((2 * j + 1) * freq); 570 for (j = 1; j < m / 8; j++) 571 tctx->cos_tabs[i][m / 4 - j] = tctx->cos_tabs[i][j]; 572 } 573 574 ff_init_ff_sine_windows(av_log2(size_m)); 575 ff_init_ff_sine_windows(av_log2(size_s / 2)); 576 ff_init_ff_sine_windows(av_log2(mtab->size)); 577 578 return 0; 579 580alloc_fail: 581 return AVERROR(ENOMEM); 582} 583 584/** 585 * Interpret the data as if it were a num_blocks x line_len[0] matrix and for 586 * each line do a cyclic permutation, i.e. 587 * abcdefghijklm -> defghijklmabc 588 * where the amount to be shifted is evaluated depending on the column. 589 */ 590static void permutate_in_line(int16_t *tab, int num_vect, int num_blocks, 591 int block_size, 592 const uint8_t line_len[2], int length_div, 593 enum TwinVQFrameType ftype) 594{ 595 int i, j; 596 597 for (i = 0; i < line_len[0]; i++) { 598 int shift; 599 600 if (num_blocks == 1 || 601 (ftype == TWINVQ_FT_LONG && num_vect % num_blocks) || 602 (ftype != TWINVQ_FT_LONG && num_vect & 1) || 603 i == line_len[1]) { 604 shift = 0; 605 } else if (ftype == TWINVQ_FT_LONG) { 606 shift = i; 607 } else 608 shift = i * i; 609 610 for (j = 0; j < num_vect && (j + num_vect * i < block_size * num_blocks); j++) 611 tab[i * num_vect + j] = i * num_vect + (j + shift) % num_vect; 612 } 613} 614 615/** 616 * Interpret the input data as in the following table: 617 * 618 * @verbatim 619 * 620 * abcdefgh 621 * ijklmnop 622 * qrstuvw 623 * x123456 624 * 625 * @endverbatim 626 * 627 * and transpose it, giving the output 628 * aiqxbjr1cks2dlt3emu4fvn5gow6hp 629 */ 630static void transpose_perm(int16_t *out, int16_t *in, int num_vect, 631 const uint8_t line_len[2], int length_div) 632{ 633 int i, j; 634 int cont = 0; 635 636 for (i = 0; i < num_vect; i++) 637 for (j = 0; j < line_len[i >= length_div]; j++) 638 out[cont++] = in[j * num_vect + i]; 639} 640 641static void linear_perm(int16_t *out, int16_t *in, int n_blocks, int size) 642{ 643 int block_size = size / n_blocks; 644 int i; 645 646 for (i = 0; i < size; i++) 647 out[i] = block_size * (in[i] % n_blocks) + in[i] / n_blocks; 648} 649 650static av_cold void construct_perm_table(TwinVQContext *tctx, 651 enum TwinVQFrameType ftype) 652{ 653 int block_size, size; 654 const TwinVQModeTab *mtab = tctx->mtab; 655 int16_t *tmp_perm = (int16_t *)tctx->tmp_buf; 656 657 if (ftype == TWINVQ_FT_PPC) { 658 size = tctx->avctx->channels; 659 block_size = mtab->ppc_shape_len; 660 } else { 661 size = tctx->avctx->channels * mtab->fmode[ftype].sub; 662 block_size = mtab->size / mtab->fmode[ftype].sub; 663 } 664 665 permutate_in_line(tmp_perm, tctx->n_div[ftype], size, 666 block_size, tctx->length[ftype], 667 tctx->length_change[ftype], ftype); 668 669 transpose_perm(tctx->permut[ftype], tmp_perm, tctx->n_div[ftype], 670 tctx->length[ftype], tctx->length_change[ftype]); 671 672 linear_perm(tctx->permut[ftype], tctx->permut[ftype], size, 673 size * block_size); 674} 675 676static av_cold void init_bitstream_params(TwinVQContext *tctx) 677{ 678 const TwinVQModeTab *mtab = tctx->mtab; 679 int n_ch = tctx->avctx->channels; 680 int total_fr_bits = tctx->avctx->bit_rate * mtab->size / 681 tctx->avctx->sample_rate; 682 683 int lsp_bits_per_block = n_ch * (mtab->lsp_bit0 + mtab->lsp_bit1 + 684 mtab->lsp_split * mtab->lsp_bit2); 685 686 int ppc_bits = n_ch * (mtab->pgain_bit + mtab->ppc_shape_bit + 687 mtab->ppc_period_bit); 688 689 int bsize_no_main_cb[3], bse_bits[3], i; 690 enum TwinVQFrameType frametype; 691 692 for (i = 0; i < 3; i++) 693 // +1 for history usage switch 694 bse_bits[i] = n_ch * 695 (mtab->fmode[i].bark_n_coef * 696 mtab->fmode[i].bark_n_bit + 1); 697 698 bsize_no_main_cb[2] = bse_bits[2] + lsp_bits_per_block + ppc_bits + 699 TWINVQ_WINDOW_TYPE_BITS + n_ch * TWINVQ_GAIN_BITS; 700 701 for (i = 0; i < 2; i++) 702 bsize_no_main_cb[i] = 703 lsp_bits_per_block + n_ch * TWINVQ_GAIN_BITS + 704 TWINVQ_WINDOW_TYPE_BITS + 705 mtab->fmode[i].sub * (bse_bits[i] + n_ch * TWINVQ_SUB_GAIN_BITS); 706 707 if (tctx->codec == TWINVQ_CODEC_METASOUND && !tctx->is_6kbps) { 708 bsize_no_main_cb[1] += 2; 709 bsize_no_main_cb[2] += 2; 710 } 711 712 // The remaining bits are all used for the main spectrum coefficients 713 for (i = 0; i < 4; i++) { 714 int bit_size, vect_size; 715 int rounded_up, rounded_down, num_rounded_down, num_rounded_up; 716 if (i == 3) { 717 bit_size = n_ch * mtab->ppc_shape_bit; 718 vect_size = n_ch * mtab->ppc_shape_len; 719 } else { 720 bit_size = total_fr_bits - bsize_no_main_cb[i]; 721 vect_size = n_ch * mtab->size; 722 } 723 724 tctx->n_div[i] = (bit_size + 13) / 14; 725 726 rounded_up = (bit_size + tctx->n_div[i] - 1) / 727 tctx->n_div[i]; 728 rounded_down = (bit_size) / tctx->n_div[i]; 729 num_rounded_down = rounded_up * tctx->n_div[i] - bit_size; 730 num_rounded_up = tctx->n_div[i] - num_rounded_down; 731 tctx->bits_main_spec[0][i][0] = (rounded_up + 1) / 2; 732 tctx->bits_main_spec[1][i][0] = rounded_up / 2; 733 tctx->bits_main_spec[0][i][1] = (rounded_down + 1) / 2; 734 tctx->bits_main_spec[1][i][1] = rounded_down / 2; 735 tctx->bits_main_spec_change[i] = num_rounded_up; 736 737 rounded_up = (vect_size + tctx->n_div[i] - 1) / 738 tctx->n_div[i]; 739 rounded_down = (vect_size) / tctx->n_div[i]; 740 num_rounded_down = rounded_up * tctx->n_div[i] - vect_size; 741 num_rounded_up = tctx->n_div[i] - num_rounded_down; 742 tctx->length[i][0] = rounded_up; 743 tctx->length[i][1] = rounded_down; 744 tctx->length_change[i] = num_rounded_up; 745 } 746 747 for (frametype = TWINVQ_FT_SHORT; frametype <= TWINVQ_FT_PPC; frametype++) 748 construct_perm_table(tctx, frametype); 749} 750 751av_cold int ff_twinvq_decode_close(AVCodecContext *avctx) 752{ 753 TwinVQContext *tctx = avctx->priv_data; 754 int i; 755 756 for (i = 0; i < 3; i++) { 757 ff_mdct_end(&tctx->mdct_ctx[i]); 758 av_free(tctx->cos_tabs[i]); 759 } 760 761 av_free(tctx->curr_frame); 762 av_free(tctx->spectrum); 763 av_free(tctx->prev_frame); 764 av_free(tctx->tmp_buf); 765 766 return 0; 767} 768 769av_cold int ff_twinvq_decode_init(AVCodecContext *avctx) 770{ 771 int ret; 772 TwinVQContext *tctx = avctx->priv_data; 773 774 tctx->avctx = avctx; 775 avctx->sample_fmt = AV_SAMPLE_FMT_FLTP; 776 777 if (!avctx->block_align) { 778 avctx->block_align = tctx->frame_size + 7 >> 3; 779 } else if (avctx->block_align * 8 < tctx->frame_size) { 780 av_log(avctx, AV_LOG_ERROR, "Block align is %d bits, expected %d\n", 781 avctx->block_align * 8, tctx->frame_size); 782 return AVERROR_INVALIDDATA; 783 } 784 tctx->frames_per_packet = avctx->block_align * 8 / tctx->frame_size; 785 if (tctx->frames_per_packet > TWINVQ_MAX_FRAMES_PER_PACKET) { 786 av_log(avctx, AV_LOG_ERROR, "Too many frames per packet (%d)\n", 787 tctx->frames_per_packet); 788 return AVERROR_INVALIDDATA; 789 } 790 791 avpriv_float_dsp_init(&tctx->fdsp, avctx->flags & CODEC_FLAG_BITEXACT); 792 if ((ret = init_mdct_win(tctx))) { 793 av_log(avctx, AV_LOG_ERROR, "Error initializing MDCT\n"); 794 ff_twinvq_decode_close(avctx); 795 return ret; 796 } 797 init_bitstream_params(tctx); 798 799 twinvq_memset_float(tctx->bark_hist[0][0], 0.1, 800 FF_ARRAY_ELEMS(tctx->bark_hist)); 801 802 return 0; 803} 804