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twinvq.c
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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 
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  */
46 static 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  */
71 static 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 
84 static 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 
95 static 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  */
115 static 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] =
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] =
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 
152 static 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  */
172 static 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 
214 static 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],
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],
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],
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  */
250 static 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 
263 static 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);
301 }
302 
303 static 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 
325 static const uint8_t wtype_to_wsize[] = { 0, 0, 2, 2, 2, 1, 0, 1, 1 };
326 
327 static 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 
378 static 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 
412 static 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;
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,
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 
473  TWINVQ_FT_MEDIUM
474 };
475 
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++) {
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  */
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_ARRAY_OR_GOTO(tctx->avctx, tctx->tmp_buf,
550  mtab->size, sizeof(*tctx->tmp_buf), alloc_fail);
551 
553  2 * mtab->size, channels * sizeof(*tctx->spectrum),
554  alloc_fail);
556  2 * mtab->size, channels * sizeof(*tctx->curr_frame),
557  alloc_fail);
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_ARRAY_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 
575  ff_init_ff_sine_windows(av_log2(size_s / 2));
577 
578  return 0;
579 
580 alloc_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  */
590 static 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  */
630 static 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 
641 static 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 
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 
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 +
700 
701  for (i = 0; i < 2; i++)
702  bsize_no_main_cb[i] =
703  lsp_bits_per_block + n_ch * TWINVQ_GAIN_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 
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_freep(&tctx->cos_tabs[i]);
759  }
760 
761  av_freep(&tctx->curr_frame);
762  av_freep(&tctx->spectrum);
763  av_freep(&tctx->prev_frame);
764  av_freep(&tctx->tmp_buf);
765 
766  return 0;
767 }
768 
770 {
771  int ret;
772  TwinVQContext *tctx = avctx->priv_data;
773 
774  tctx->avctx = avctx;
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;
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 
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 }