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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 
23 #include "libavutil/float_dsp.h"
24 #include "avcodec.h"
25 #include "get_bits.h"
26 #include "fft.h"
27 #include "internal.h"
28 #include "lsp.h"
29 #include "sinewin.h"
30 
31 #include <math.h>
32 #include <stdint.h>
33 
34 #include "twinvq_data.h"
35 
36 enum FrameType {
37  FT_SHORT = 0, ///< Short frame (divided in n sub-blocks)
38  FT_MEDIUM, ///< Medium frame (divided in m<n sub-blocks)
39  FT_LONG, ///< Long frame (single sub-block + PPC)
40  FT_PPC, ///< Periodic Peak Component (part of the long frame)
41 };
42 
43 /**
44  * Parameters and tables that are different for each frame type
45  */
46 struct FrameMode {
47  uint8_t sub; ///< Number subblocks in each frame
48  const uint16_t *bark_tab;
49 
50  /** number of distinct bark scale envelope values */
52 
53  const int16_t *bark_cb; ///< codebook for the bark scale envelope (BSE)
54  uint8_t bark_n_coef;///< number of BSE CB coefficients to read
55  uint8_t bark_n_bit; ///< number of bits of the BSE coefs
56 
57  //@{
58  /** main codebooks for spectrum data */
59  const int16_t *cb0;
60  const int16_t *cb1;
61  //@}
62 
63  uint8_t cb_len_read; ///< number of spectrum coefficients to read
64 };
65 
66 /**
67  * Parameters and tables that are different for every combination of
68  * bitrate/sample rate
69  */
70 typedef struct {
71  struct FrameMode fmode[3]; ///< frame type-dependant parameters
72 
73  uint16_t size; ///< frame size in samples
74  uint8_t n_lsp; ///< number of lsp coefficients
75  const float *lspcodebook;
76 
77  /* number of bits of the different LSP CB coefficients */
81 
82  uint8_t lsp_split; ///< number of CB entries for the LSP decoding
83  const int16_t *ppc_shape_cb; ///< PPC shape CB
84 
85  /** number of the bits for the PPC period value */
87 
88  uint8_t ppc_shape_bit; ///< number of bits of the PPC shape CB coeffs
89  uint8_t ppc_shape_len; ///< size of PPC shape CB
90  uint8_t pgain_bit; ///< bits for PPC gain
91 
92  /** constant for peak period to peak width conversion */
93  uint16_t peak_per2wid;
94 } ModeTab;
95 
96 static const ModeTab mode_08_08 = {
97  {
98  { 8, bark_tab_s08_64, 10, tab.fcb08s , 1, 5, tab.cb0808s0, tab.cb0808s1, 18},
99  { 2, bark_tab_m08_256, 20, tab.fcb08m , 2, 5, tab.cb0808m0, tab.cb0808m1, 16},
100  { 1, bark_tab_l08_512, 30, tab.fcb08l , 3, 6, tab.cb0808l0, tab.cb0808l1, 17}
101  },
102  512 , 12, tab.lsp08, 1, 5, 3, 3, tab.shape08 , 8, 28, 20, 6, 40
103 };
104 
105 static const ModeTab mode_11_08 = {
106  {
107  { 8, bark_tab_s11_64, 10, tab.fcb11s , 1, 5, tab.cb1108s0, tab.cb1108s1, 29},
108  { 2, bark_tab_m11_256, 20, tab.fcb11m , 2, 5, tab.cb1108m0, tab.cb1108m1, 24},
109  { 1, bark_tab_l11_512, 30, tab.fcb11l , 3, 6, tab.cb1108l0, tab.cb1108l1, 27}
110  },
111  512 , 16, tab.lsp11, 1, 6, 4, 3, tab.shape11 , 9, 36, 30, 7, 90
112 };
113 
114 static const ModeTab mode_11_10 = {
115  {
116  { 8, bark_tab_s11_64, 10, tab.fcb11s , 1, 5, tab.cb1110s0, tab.cb1110s1, 21},
117  { 2, bark_tab_m11_256, 20, tab.fcb11m , 2, 5, tab.cb1110m0, tab.cb1110m1, 18},
118  { 1, bark_tab_l11_512, 30, tab.fcb11l , 3, 6, tab.cb1110l0, tab.cb1110l1, 20}
119  },
120  512 , 16, tab.lsp11, 1, 6, 4, 3, tab.shape11 , 9, 36, 30, 7, 90
121 };
122 
123 static const ModeTab mode_16_16 = {
124  {
125  { 8, bark_tab_s16_128, 10, tab.fcb16s , 1, 5, tab.cb1616s0, tab.cb1616s1, 16},
126  { 2, bark_tab_m16_512, 20, tab.fcb16m , 2, 5, tab.cb1616m0, tab.cb1616m1, 15},
127  { 1, bark_tab_l16_1024,30, tab.fcb16l , 3, 6, tab.cb1616l0, tab.cb1616l1, 16}
128  },
129  1024, 16, tab.lsp16, 1, 6, 4, 3, tab.shape16 , 9, 56, 60, 7, 180
130 };
131 
132 static const ModeTab mode_22_20 = {
133  {
134  { 8, bark_tab_s22_128, 10, tab.fcb22s_1, 1, 6, tab.cb2220s0, tab.cb2220s1, 18},
135  { 2, bark_tab_m22_512, 20, tab.fcb22m_1, 2, 6, tab.cb2220m0, tab.cb2220m1, 17},
136  { 1, bark_tab_l22_1024,32, tab.fcb22l_1, 4, 6, tab.cb2220l0, tab.cb2220l1, 18}
137  },
138  1024, 16, tab.lsp22_1, 1, 6, 4, 3, tab.shape22_1, 9, 56, 36, 7, 144
139 };
140 
141 static const ModeTab mode_22_24 = {
142  {
143  { 8, bark_tab_s22_128, 10, tab.fcb22s_1, 1, 6, tab.cb2224s0, tab.cb2224s1, 15},
144  { 2, bark_tab_m22_512, 20, tab.fcb22m_1, 2, 6, tab.cb2224m0, tab.cb2224m1, 14},
145  { 1, bark_tab_l22_1024,32, tab.fcb22l_1, 4, 6, tab.cb2224l0, tab.cb2224l1, 15}
146  },
147  1024, 16, tab.lsp22_1, 1, 6, 4, 3, tab.shape22_1, 9, 56, 36, 7, 144
148 };
149 
150 static const ModeTab mode_22_32 = {
151  {
152  { 4, bark_tab_s22_128, 10, tab.fcb22s_2, 1, 6, tab.cb2232s0, tab.cb2232s1, 11},
153  { 2, bark_tab_m22_256, 20, tab.fcb22m_2, 2, 6, tab.cb2232m0, tab.cb2232m1, 11},
154  { 1, bark_tab_l22_512, 32, tab.fcb22l_2, 4, 6, tab.cb2232l0, tab.cb2232l1, 12}
155  },
156  512 , 16, tab.lsp22_2, 1, 6, 4, 4, tab.shape22_2, 9, 56, 36, 7, 72
157 };
158 
159 static const ModeTab mode_44_40 = {
160  {
161  {16, bark_tab_s44_128, 10, tab.fcb44s , 1, 6, tab.cb4440s0, tab.cb4440s1, 18},
162  { 4, bark_tab_m44_512, 20, tab.fcb44m , 2, 6, tab.cb4440m0, tab.cb4440m1, 17},
163  { 1, bark_tab_l44_2048,40, tab.fcb44l , 4, 6, tab.cb4440l0, tab.cb4440l1, 17}
164  },
165  2048, 20, tab.lsp44, 1, 6, 4, 4, tab.shape44 , 9, 84, 54, 7, 432
166 };
167 
168 static const ModeTab mode_44_48 = {
169  {
170  {16, bark_tab_s44_128, 10, tab.fcb44s , 1, 6, tab.cb4448s0, tab.cb4448s1, 15},
171  { 4, bark_tab_m44_512, 20, tab.fcb44m , 2, 6, tab.cb4448m0, tab.cb4448m1, 14},
172  { 1, bark_tab_l44_2048,40, tab.fcb44l , 4, 6, tab.cb4448l0, tab.cb4448l1, 14}
173  },
174  2048, 20, tab.lsp44, 1, 6, 4, 4, tab.shape44 , 9, 84, 54, 7, 432
175 };
176 
177 typedef struct TwinContext {
181 
182  const ModeTab *mtab;
183 
184  // history
185  float lsp_hist[2][20]; ///< LSP coefficients of the last frame
186  float bark_hist[3][2][40]; ///< BSE coefficients of last frame
187 
188  // bitstream parameters
189  int16_t permut[4][4096];
190  uint8_t length[4][2]; ///< main codebook stride
192  uint8_t bits_main_spec[2][4][2]; ///< bits for the main codebook
194  int n_div[4];
195 
196  float *spectrum;
197  float *curr_frame; ///< non-interleaved output
198  float *prev_frame; ///< non-interleaved previous frame
201 
202  float *cos_tabs[3];
203 
204  // scratch buffers
205  float *tmp_buf;
206 } TwinContext;
207 
208 #define PPC_SHAPE_CB_SIZE 64
209 #define PPC_SHAPE_LEN_MAX 60
210 #define SUB_AMP_MAX 4500.0
211 #define MULAW_MU 100.0
212 #define GAIN_BITS 8
213 #define AMP_MAX 13000.0
214 #define SUB_GAIN_BITS 5
215 #define WINDOW_TYPE_BITS 4
216 #define PGAIN_MU 200
217 #define LSP_COEFS_MAX 20
218 #define LSP_SPLIT_MAX 4
219 #define CHANNELS_MAX 2
220 #define SUBBLOCKS_MAX 16
221 #define BARK_N_COEF_MAX 4
222 
223 /** @note not speed critical, hence not optimized */
224 static void memset_float(float *buf, float val, int size)
225 {
226  while (size--)
227  *buf++ = val;
228 }
229 
230 /**
231  * Evaluate a single LPC amplitude spectrum envelope coefficient from the line
232  * spectrum pairs.
233  *
234  * @param lsp a vector of the cosinus of the LSP values
235  * @param cos_val cos(PI*i/N) where i is the index of the LPC amplitude
236  * @param order the order of the LSP (and the size of the *lsp buffer). Must
237  * be a multiple of four.
238  * @return the LPC value
239  *
240  * @todo reuse code from Vorbis decoder: vorbis_floor0_decode
241  */
242 static float eval_lpc_spectrum(const float *lsp, float cos_val, int order)
243 {
244  int j;
245  float p = 0.5f;
246  float q = 0.5f;
247  float two_cos_w = 2.0f*cos_val;
248 
249  for (j = 0; j + 1 < order; j += 2*2) {
250  // Unroll the loop once since order is a multiple of four
251  q *= lsp[j ] - two_cos_w;
252  p *= lsp[j+1] - two_cos_w;
253 
254  q *= lsp[j+2] - two_cos_w;
255  p *= lsp[j+3] - two_cos_w;
256  }
257 
258  p *= p * (2.0f - two_cos_w);
259  q *= q * (2.0f + two_cos_w);
260 
261  return 0.5 / (p + q);
262 }
263 
264 /**
265  * Evaluate the LPC amplitude spectrum envelope from the line spectrum pairs.
266  */
267 static void eval_lpcenv(TwinContext *tctx, const float *cos_vals, float *lpc)
268 {
269  int i;
270  const ModeTab *mtab = tctx->mtab;
271  int size_s = mtab->size / mtab->fmode[FT_SHORT].sub;
272 
273  for (i = 0; i < size_s/2; i++) {
274  float cos_i = tctx->cos_tabs[0][i];
275  lpc[i] = eval_lpc_spectrum(cos_vals, cos_i, mtab->n_lsp);
276  lpc[size_s-i-1] = eval_lpc_spectrum(cos_vals, -cos_i, mtab->n_lsp);
277  }
278 }
279 
280 static void interpolate(float *out, float v1, float v2, int size)
281 {
282  int i;
283  float step = (v1 - v2)/(size + 1);
284 
285  for (i = 0; i < size; i++) {
286  v2 += step;
287  out[i] = v2;
288  }
289 }
290 
291 static inline float get_cos(int idx, int part, const float *cos_tab, int size)
292 {
293  return part ? -cos_tab[size - idx - 1] :
294  cos_tab[ idx ];
295 }
296 
297 /**
298  * Evaluate the LPC amplitude spectrum envelope from the line spectrum pairs.
299  * Probably for speed reasons, the coefficients are evaluated as
300  * siiiibiiiisiiiibiiiisiiiibiiiisiiiibiiiis ...
301  * where s is an evaluated value, i is a value interpolated from the others
302  * and b might be either calculated or interpolated, depending on an
303  * unexplained condition.
304  *
305  * @param step the size of a block "siiiibiiii"
306  * @param in the cosinus of the LSP data
307  * @param part is 0 for 0...PI (positive cossinus values) and 1 for PI...2PI
308  (negative cossinus values)
309  * @param size the size of the whole output
310  */
311 static inline void eval_lpcenv_or_interp(TwinContext *tctx,
312  enum FrameType ftype,
313  float *out, const float *in,
314  int size, int step, int part)
315 {
316  int i;
317  const ModeTab *mtab = tctx->mtab;
318  const float *cos_tab = tctx->cos_tabs[ftype];
319 
320  // Fill the 's'
321  for (i = 0; i < size; i += step)
322  out[i] =
324  get_cos(i, part, cos_tab, size),
325  mtab->n_lsp);
326 
327  // Fill the 'iiiibiiii'
328  for (i = step; i <= size - 2*step; i += step) {
329  if (out[i + step] + out[i - step] > 1.95*out[i] ||
330  out[i + step] >= out[i - step]) {
331  interpolate(out + i - step + 1, out[i], out[i-step], step - 1);
332  } else {
333  out[i - step/2] =
335  get_cos(i-step/2, part, cos_tab, size),
336  mtab->n_lsp);
337  interpolate(out + i - step + 1, out[i-step/2], out[i-step ], step/2 - 1);
338  interpolate(out + i - step/2 + 1, out[i ], out[i-step/2], step/2 - 1);
339  }
340  }
341 
342  interpolate(out + size - 2*step + 1, out[size-step], out[size - 2*step], step - 1);
343 }
344 
345 static void eval_lpcenv_2parts(TwinContext *tctx, enum FrameType ftype,
346  const float *buf, float *lpc,
347  int size, int step)
348 {
349  eval_lpcenv_or_interp(tctx, ftype, lpc , buf, size/2, step, 0);
350  eval_lpcenv_or_interp(tctx, ftype, lpc + size/2, buf, size/2, 2*step, 1);
351 
352  interpolate(lpc+size/2-step+1, lpc[size/2], lpc[size/2-step], step);
353 
354  memset_float(lpc + size - 2*step + 1, lpc[size - 2*step], 2*step - 1);
355 }
356 
357 /**
358  * Inverse quantization. Read CB coefficients for cb1 and cb2 from the
359  * bitstream, sum the corresponding vectors and write the result to *out
360  * after permutation.
361  */
362 static void dequant(TwinContext *tctx, GetBitContext *gb, float *out,
363  enum FrameType ftype,
364  const int16_t *cb0, const int16_t *cb1, int cb_len)
365 {
366  int pos = 0;
367  int i, j;
368 
369  for (i = 0; i < tctx->n_div[ftype]; i++) {
370  int tmp0, tmp1;
371  int sign0 = 1;
372  int sign1 = 1;
373  const int16_t *tab0, *tab1;
374  int length = tctx->length[ftype][i >= tctx->length_change[ftype]];
375  int bitstream_second_part = (i >= tctx->bits_main_spec_change[ftype]);
376 
377  int bits = tctx->bits_main_spec[0][ftype][bitstream_second_part];
378  if (bits == 7) {
379  if (get_bits1(gb))
380  sign0 = -1;
381  bits = 6;
382  }
383  tmp0 = get_bits(gb, bits);
384 
385  bits = tctx->bits_main_spec[1][ftype][bitstream_second_part];
386 
387  if (bits == 7) {
388  if (get_bits1(gb))
389  sign1 = -1;
390 
391  bits = 6;
392  }
393  tmp1 = get_bits(gb, bits);
394 
395  tab0 = cb0 + tmp0*cb_len;
396  tab1 = cb1 + tmp1*cb_len;
397 
398  for (j = 0; j < length; j++)
399  out[tctx->permut[ftype][pos+j]] = sign0*tab0[j] + sign1*tab1[j];
400 
401  pos += length;
402  }
403 
404 }
405 
406 static inline float mulawinv(float y, float clip, float mu)
407 {
408  y = av_clipf(y/clip, -1, 1);
409  return clip * FFSIGN(y) * (exp(log(1+mu) * fabs(y)) - 1) / mu;
410 }
411 
412 /**
413  * Evaluate a*b/400 rounded to the nearest integer. When, for example,
414  * a*b == 200 and the nearest integer is ill-defined, use a table to emulate
415  * the following broken float-based implementation used by the binary decoder:
416  *
417  * @code
418  * static int very_broken_op(int a, int b)
419  * {
420  * static float test; // Ugh, force gcc to do the division first...
421  *
422  * test = a/400.;
423  * return b * test + 0.5;
424  * }
425  * @endcode
426  *
427  * @note if this function is replaced by just ROUNDED_DIV(a*b,400.), the stddev
428  * between the original file (before encoding with Yamaha encoder) and the
429  * decoded output increases, which leads one to believe that the encoder expects
430  * exactly this broken calculation.
431  */
432 static int very_broken_op(int a, int b)
433 {
434  int x = a*b + 200;
435  int size;
436  const uint8_t *rtab;
437 
438  if (x%400 || b%5)
439  return x/400;
440 
441  x /= 400;
442 
443  size = tabs[b/5].size;
444  rtab = tabs[b/5].tab;
445  return x - rtab[size*av_log2(2*(x - 1)/size)+(x - 1)%size];
446 }
447 
448 /**
449  * Sum to data a periodic peak of a given period, width and shape.
450  *
451  * @param period the period of the peak divised by 400.0
452  */
453 static void add_peak(int period, int width, const float *shape,
454  float ppc_gain, float *speech, int len)
455 {
456  int i, j;
457 
458  const float *shape_end = shape + len;
459  int center;
460 
461  // First peak centered around zero
462  for (i = 0; i < width/2; i++)
463  speech[i] += ppc_gain * *shape++;
464 
465  for (i = 1; i < ROUNDED_DIV(len,width) ; i++) {
466  center = very_broken_op(period, i);
467  for (j = -width/2; j < (width+1)/2; j++)
468  speech[j+center] += ppc_gain * *shape++;
469  }
470 
471  // For the last block, be careful not to go beyond the end of the buffer
472  center = very_broken_op(period, i);
473  for (j = -width/2; j < (width + 1)/2 && shape < shape_end; j++)
474  speech[j+center] += ppc_gain * *shape++;
475 }
476 
477 static void decode_ppc(TwinContext *tctx, int period_coef, const float *shape,
478  float ppc_gain, float *speech)
479 {
480  const ModeTab *mtab = tctx->mtab;
481  int isampf = tctx->avctx->sample_rate/1000;
482  int ibps = tctx->avctx->bit_rate/(1000 * tctx->avctx->channels);
483  int min_period = ROUNDED_DIV( 40*2*mtab->size, isampf);
484  int max_period = ROUNDED_DIV(6*40*2*mtab->size, isampf);
485  int period_range = max_period - min_period;
486 
487  // This is actually the period multiplied by 400. It is just linearly coded
488  // between its maximum and minimum value.
489  int period = min_period +
490  ROUNDED_DIV(period_coef*period_range, (1 << mtab->ppc_period_bit) - 1);
491  int width;
492 
493  if (isampf == 22 && ibps == 32) {
494  // For some unknown reason, NTT decided to code this case differently...
495  width = ROUNDED_DIV((period + 800)* mtab->peak_per2wid, 400*mtab->size);
496  } else
497  width = (period )* mtab->peak_per2wid/(400*mtab->size);
498 
499  add_peak(period, width, shape, ppc_gain, speech, mtab->ppc_shape_len);
500 }
501 
502 static void dec_gain(TwinContext *tctx, GetBitContext *gb, enum FrameType ftype,
503  float *out)
504 {
505  const ModeTab *mtab = tctx->mtab;
506  int i, j;
507  int sub = mtab->fmode[ftype].sub;
508  float step = AMP_MAX / ((1 << GAIN_BITS) - 1);
509  float sub_step = SUB_AMP_MAX / ((1 << SUB_GAIN_BITS) - 1);
510 
511  if (ftype == FT_LONG) {
512  for (i = 0; i < tctx->avctx->channels; i++)
513  out[i] = (1./(1<<13)) *
514  mulawinv(step * 0.5 + step * get_bits(gb, GAIN_BITS),
515  AMP_MAX, MULAW_MU);
516  } else {
517  for (i = 0; i < tctx->avctx->channels; i++) {
518  float val = (1./(1<<23)) *
519  mulawinv(step * 0.5 + step * get_bits(gb, GAIN_BITS),
520  AMP_MAX, MULAW_MU);
521 
522  for (j = 0; j < sub; j++) {
523  out[i*sub + j] =
524  val*mulawinv(sub_step* 0.5 +
525  sub_step* get_bits(gb, SUB_GAIN_BITS),
527  }
528  }
529  }
530 }
531 
532 /**
533  * Rearrange the LSP coefficients so that they have a minimum distance of
534  * min_dist. This function does it exactly as described in section of 3.2.4
535  * of the G.729 specification (but interestingly is different from what the
536  * reference decoder actually does).
537  */
538 static void rearrange_lsp(int order, float *lsp, float min_dist)
539 {
540  int i;
541  float min_dist2 = min_dist * 0.5;
542  for (i = 1; i < order; i++)
543  if (lsp[i] - lsp[i-1] < min_dist) {
544  float avg = (lsp[i] + lsp[i-1]) * 0.5;
545 
546  lsp[i-1] = avg - min_dist2;
547  lsp[i ] = avg + min_dist2;
548  }
549 }
550 
551 static void decode_lsp(TwinContext *tctx, int lpc_idx1, uint8_t *lpc_idx2,
552  int lpc_hist_idx, float *lsp, float *hist)
553 {
554  const ModeTab *mtab = tctx->mtab;
555  int i, j;
556 
557  const float *cb = mtab->lspcodebook;
558  const float *cb2 = cb + (1 << mtab->lsp_bit1)*mtab->n_lsp;
559  const float *cb3 = cb2 + (1 << mtab->lsp_bit2)*mtab->n_lsp;
560 
561  const int8_t funny_rounding[4] = {
562  -2,
563  mtab->lsp_split == 4 ? -2 : 1,
564  mtab->lsp_split == 4 ? -2 : 1,
565  0
566  };
567 
568  j = 0;
569  for (i = 0; i < mtab->lsp_split; i++) {
570  int chunk_end = ((i + 1)*mtab->n_lsp + funny_rounding[i])/mtab->lsp_split;
571  for (; j < chunk_end; j++)
572  lsp[j] = cb [lpc_idx1 * mtab->n_lsp + j] +
573  cb2[lpc_idx2[i] * mtab->n_lsp + j];
574  }
575 
576  rearrange_lsp(mtab->n_lsp, lsp, 0.0001);
577 
578  for (i = 0; i < mtab->n_lsp; i++) {
579  float tmp1 = 1. - cb3[lpc_hist_idx*mtab->n_lsp + i];
580  float tmp2 = hist[i] * cb3[lpc_hist_idx*mtab->n_lsp + i];
581  hist[i] = lsp[i];
582  lsp[i] = lsp[i] * tmp1 + tmp2;
583  }
584 
585  rearrange_lsp(mtab->n_lsp, lsp, 0.0001);
586  rearrange_lsp(mtab->n_lsp, lsp, 0.000095);
588 }
589 
590 static void dec_lpc_spectrum_inv(TwinContext *tctx, float *lsp,
591  enum FrameType ftype, float *lpc)
592 {
593  int i;
594  int size = tctx->mtab->size / tctx->mtab->fmode[ftype].sub;
595 
596  for (i = 0; i < tctx->mtab->n_lsp; i++)
597  lsp[i] = 2*cos(lsp[i]);
598 
599  switch (ftype) {
600  case FT_LONG:
601  eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 8);
602  break;
603  case FT_MEDIUM:
604  eval_lpcenv_2parts(tctx, ftype, lsp, lpc, size, 2);
605  break;
606  case FT_SHORT:
607  eval_lpcenv(tctx, lsp, lpc);
608  break;
609  }
610 }
611 
612 static void imdct_and_window(TwinContext *tctx, enum FrameType ftype, int wtype,
613  float *in, float *prev, int ch)
614 {
615  FFTContext *mdct = &tctx->mdct_ctx[ftype];
616  const ModeTab *mtab = tctx->mtab;
617  int bsize = mtab->size / mtab->fmode[ftype].sub;
618  int size = mtab->size;
619  float *buf1 = tctx->tmp_buf;
620  int j;
621  int wsize; // Window size
622  float *out = tctx->curr_frame + 2*ch*mtab->size;
623  float *out2 = out;
624  float *prev_buf;
625  int first_wsize;
626 
627  static const uint8_t wtype_to_wsize[] = {0, 0, 2, 2, 2, 1, 0, 1, 1};
628  int types_sizes[] = {
629  mtab->size / mtab->fmode[FT_LONG ].sub,
630  mtab->size / mtab->fmode[FT_MEDIUM].sub,
631  mtab->size / (2*mtab->fmode[FT_SHORT ].sub),
632  };
633 
634  wsize = types_sizes[wtype_to_wsize[wtype]];
635  first_wsize = wsize;
636  prev_buf = prev + (size - bsize)/2;
637 
638  for (j = 0; j < mtab->fmode[ftype].sub; j++) {
639  int sub_wtype = ftype == FT_MEDIUM ? 8 : wtype;
640 
641  if (!j && wtype == 4)
642  sub_wtype = 4;
643  else if (j == mtab->fmode[ftype].sub-1 && wtype == 7)
644  sub_wtype = 7;
645 
646  wsize = types_sizes[wtype_to_wsize[sub_wtype]];
647 
648  mdct->imdct_half(mdct, buf1 + bsize*j, in + bsize*j);
649 
650  tctx->fdsp.vector_fmul_window(out2, prev_buf + (bsize-wsize) / 2,
651  buf1 + bsize * j,
652  ff_sine_windows[av_log2(wsize)],
653  wsize / 2);
654  out2 += wsize;
655 
656  memcpy(out2, buf1 + bsize*j + wsize/2, (bsize - wsize/2)*sizeof(float));
657 
658  out2 += ftype == FT_MEDIUM ? (bsize-wsize)/2 : bsize - wsize;
659 
660  prev_buf = buf1 + bsize*j + bsize/2;
661  }
662 
663  tctx->last_block_pos[ch] = (size + first_wsize)/2;
664 }
665 
666 static void imdct_output(TwinContext *tctx, enum FrameType ftype, int wtype,
667  float **out)
668 {
669  const ModeTab *mtab = tctx->mtab;
670  int size1, size2;
671  float *prev_buf = tctx->prev_frame + tctx->last_block_pos[0];
672  int i;
673 
674  for (i = 0; i < tctx->avctx->channels; i++) {
675  imdct_and_window(tctx, ftype, wtype,
676  tctx->spectrum + i*mtab->size,
677  prev_buf + 2*i*mtab->size,
678  i);
679  }
680 
681  if (!out)
682  return;
683 
684  size2 = tctx->last_block_pos[0];
685  size1 = mtab->size - size2;
686 
687  memcpy(&out[0][0 ], prev_buf, size1 * sizeof(out[0][0]));
688  memcpy(&out[0][size1], tctx->curr_frame, size2 * sizeof(out[0][0]));
689 
690  if (tctx->avctx->channels == 2) {
691  memcpy(&out[1][0], &prev_buf[2*mtab->size], size1 * sizeof(out[1][0]));
692  memcpy(&out[1][size1], &tctx->curr_frame[2*mtab->size], size2 * sizeof(out[1][0]));
693  tctx->fdsp.butterflies_float(out[0], out[1], mtab->size);
694  }
695 }
696 
697 static void dec_bark_env(TwinContext *tctx, const uint8_t *in, int use_hist,
698  int ch, float *out, float gain, enum FrameType ftype)
699 {
700  const ModeTab *mtab = tctx->mtab;
701  int i,j;
702  float *hist = tctx->bark_hist[ftype][ch];
703  float val = ((const float []) {0.4, 0.35, 0.28})[ftype];
704  int bark_n_coef = mtab->fmode[ftype].bark_n_coef;
705  int fw_cb_len = mtab->fmode[ftype].bark_env_size / bark_n_coef;
706  int idx = 0;
707 
708  for (i = 0; i < fw_cb_len; i++)
709  for (j = 0; j < bark_n_coef; j++, idx++) {
710  float tmp2 =
711  mtab->fmode[ftype].bark_cb[fw_cb_len*in[j] + i] * (1./4096);
712  float st = use_hist ?
713  (1. - val) * tmp2 + val*hist[idx] + 1. : tmp2 + 1.;
714 
715  hist[idx] = tmp2;
716  if (st < -1.) st = 1.;
717 
718  memset_float(out, st * gain, mtab->fmode[ftype].bark_tab[idx]);
719  out += mtab->fmode[ftype].bark_tab[idx];
720  }
721 
722 }
723 
725  float *out, enum FrameType ftype)
726 {
727  const ModeTab *mtab = tctx->mtab;
728  int channels = tctx->avctx->channels;
729  int sub = mtab->fmode[ftype].sub;
730  int block_size = mtab->size / sub;
731  float gain[CHANNELS_MAX*SUBBLOCKS_MAX];
732  float ppc_shape[PPC_SHAPE_LEN_MAX * CHANNELS_MAX * 4];
734  uint8_t bark_use_hist[CHANNELS_MAX][SUBBLOCKS_MAX];
735 
736  uint8_t lpc_idx1[CHANNELS_MAX];
738  uint8_t lpc_hist_idx[CHANNELS_MAX];
739 
740  int i, j, k;
741 
742  dequant(tctx, gb, out, ftype,
743  mtab->fmode[ftype].cb0, mtab->fmode[ftype].cb1,
744  mtab->fmode[ftype].cb_len_read);
745 
746  for (i = 0; i < channels; i++)
747  for (j = 0; j < sub; j++)
748  for (k = 0; k < mtab->fmode[ftype].bark_n_coef; k++)
749  bark1[i][j][k] =
750  get_bits(gb, mtab->fmode[ftype].bark_n_bit);
751 
752  for (i = 0; i < channels; i++)
753  for (j = 0; j < sub; j++)
754  bark_use_hist[i][j] = get_bits1(gb);
755 
756  dec_gain(tctx, gb, ftype, gain);
757 
758  for (i = 0; i < channels; i++) {
759  lpc_hist_idx[i] = get_bits(gb, tctx->mtab->lsp_bit0);
760  lpc_idx1 [i] = get_bits(gb, tctx->mtab->lsp_bit1);
761 
762  for (j = 0; j < tctx->mtab->lsp_split; j++)
763  lpc_idx2[i][j] = get_bits(gb, tctx->mtab->lsp_bit2);
764  }
765 
766  if (ftype == FT_LONG) {
767  int cb_len_p = (tctx->n_div[3] + mtab->ppc_shape_len*channels - 1)/
768  tctx->n_div[3];
769  dequant(tctx, gb, ppc_shape, FT_PPC, mtab->ppc_shape_cb,
770  mtab->ppc_shape_cb + cb_len_p*PPC_SHAPE_CB_SIZE, cb_len_p);
771  }
772 
773  for (i = 0; i < channels; i++) {
774  float *chunk = out + mtab->size * i;
775  float lsp[LSP_COEFS_MAX];
776 
777  for (j = 0; j < sub; j++) {
778  dec_bark_env(tctx, bark1[i][j], bark_use_hist[i][j], i,
779  tctx->tmp_buf, gain[sub*i+j], ftype);
780 
781  tctx->fdsp.vector_fmul(chunk + block_size*j, chunk + block_size*j,
782  tctx->tmp_buf, block_size);
783 
784  }
785 
786  if (ftype == FT_LONG) {
787  float pgain_step = 25000. / ((1 << mtab->pgain_bit) - 1);
788  int p_coef = get_bits(gb, tctx->mtab->ppc_period_bit);
789  int g_coef = get_bits(gb, tctx->mtab->pgain_bit);
790  float v = 1./8192*
791  mulawinv(pgain_step*g_coef+ pgain_step/2, 25000., PGAIN_MU);
792 
793  decode_ppc(tctx, p_coef, ppc_shape + i*mtab->ppc_shape_len, v,
794  chunk);
795  }
796 
797  decode_lsp(tctx, lpc_idx1[i], lpc_idx2[i], lpc_hist_idx[i], lsp,
798  tctx->lsp_hist[i]);
799 
800  dec_lpc_spectrum_inv(tctx, lsp, ftype, tctx->tmp_buf);
801 
802  for (j = 0; j < mtab->fmode[ftype].sub; j++) {
803  tctx->fdsp.vector_fmul(chunk, chunk, tctx->tmp_buf, block_size);
804  chunk += block_size;
805  }
806  }
807 }
808 
809 static int twin_decode_frame(AVCodecContext * avctx, void *data,
810  int *got_frame_ptr, AVPacket *avpkt)
811 {
812  AVFrame *frame = data;
813  const uint8_t *buf = avpkt->data;
814  int buf_size = avpkt->size;
815  TwinContext *tctx = avctx->priv_data;
816  GetBitContext gb;
817  const ModeTab *mtab = tctx->mtab;
818  float **out = NULL;
819  enum FrameType ftype;
820  int window_type, ret;
821  static const enum FrameType wtype_to_ftype_table[] = {
823  FT_MEDIUM, FT_LONG, FT_LONG, FT_MEDIUM, FT_MEDIUM
824  };
825 
826  if (buf_size*8 < avctx->bit_rate*mtab->size/avctx->sample_rate + 8) {
827  av_log(avctx, AV_LOG_ERROR,
828  "Frame too small (%d bytes). Truncated file?\n", buf_size);
829  return AVERROR(EINVAL);
830  }
831 
832  /* get output buffer */
833  if (tctx->discarded_packets >= 2) {
834  frame->nb_samples = mtab->size;
835  if ((ret = ff_get_buffer(avctx, frame)) < 0) {
836  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
837  return ret;
838  }
839  out = (float **)frame->extended_data;
840  }
841 
842  init_get_bits(&gb, buf, buf_size * 8);
843  skip_bits(&gb, get_bits(&gb, 8));
844  window_type = get_bits(&gb, WINDOW_TYPE_BITS);
845 
846  if (window_type > 8) {
847  av_log(avctx, AV_LOG_ERROR, "Invalid window type, broken sample?\n");
848  return -1;
849  }
850 
851  ftype = wtype_to_ftype_table[window_type];
852 
853  read_and_decode_spectrum(tctx, &gb, tctx->spectrum, ftype);
854 
855  imdct_output(tctx, ftype, window_type, out);
856 
857  FFSWAP(float*, tctx->curr_frame, tctx->prev_frame);
858 
859  if (tctx->discarded_packets < 2) {
860  tctx->discarded_packets++;
861  *got_frame_ptr = 0;
862  return buf_size;
863  }
864 
865  *got_frame_ptr = 1;
866 
867  return buf_size;
868 }
869 
870 /**
871  * Init IMDCT and windowing tables
872  */
874 {
875  int i, j, ret;
876  const ModeTab *mtab = tctx->mtab;
877  int size_s = mtab->size / mtab->fmode[FT_SHORT].sub;
878  int size_m = mtab->size / mtab->fmode[FT_MEDIUM].sub;
879  int channels = tctx->avctx->channels;
880  float norm = channels == 1 ? 2. : 1.;
881 
882  for (i = 0; i < 3; i++) {
883  int bsize = tctx->mtab->size/tctx->mtab->fmode[i].sub;
884  if ((ret = ff_mdct_init(&tctx->mdct_ctx[i], av_log2(bsize) + 1, 1,
885  -sqrt(norm/bsize) / (1<<15))))
886  return ret;
887  }
888 
889  FF_ALLOC_OR_GOTO(tctx->avctx, tctx->tmp_buf,
890  mtab->size * sizeof(*tctx->tmp_buf), alloc_fail);
891 
892  FF_ALLOC_OR_GOTO(tctx->avctx, tctx->spectrum,
893  2 * mtab->size * channels * sizeof(*tctx->spectrum),
894  alloc_fail);
895  FF_ALLOC_OR_GOTO(tctx->avctx, tctx->curr_frame,
896  2 * mtab->size * channels * sizeof(*tctx->curr_frame),
897  alloc_fail);
898  FF_ALLOC_OR_GOTO(tctx->avctx, tctx->prev_frame,
899  2 * mtab->size * channels * sizeof(*tctx->prev_frame),
900  alloc_fail);
901 
902  for (i = 0; i < 3; i++) {
903  int m = 4*mtab->size/mtab->fmode[i].sub;
904  double freq = 2*M_PI/m;
905  FF_ALLOC_OR_GOTO(tctx->avctx, tctx->cos_tabs[i],
906  (m / 4) * sizeof(*tctx->cos_tabs[i]), alloc_fail);
907 
908  for (j = 0; j <= m/8; j++)
909  tctx->cos_tabs[i][j] = cos((2*j + 1)*freq);
910  for (j = 1; j < m/8; j++)
911  tctx->cos_tabs[i][m/4-j] = tctx->cos_tabs[i][j];
912  }
913 
914 
916  ff_init_ff_sine_windows(av_log2(size_s/2));
918 
919  return 0;
920 alloc_fail:
921  return AVERROR(ENOMEM);
922 }
923 
924 /**
925  * Interpret the data as if it were a num_blocks x line_len[0] matrix and for
926  * each line do a cyclic permutation, i.e.
927  * abcdefghijklm -> defghijklmabc
928  * where the amount to be shifted is evaluated depending on the column.
929  */
930 static void permutate_in_line(int16_t *tab, int num_vect, int num_blocks,
931  int block_size,
932  const uint8_t line_len[2], int length_div,
933  enum FrameType ftype)
934 
935 {
936  int i,j;
937 
938  for (i = 0; i < line_len[0]; i++) {
939  int shift;
940 
941  if (num_blocks == 1 ||
942  (ftype == FT_LONG && num_vect % num_blocks) ||
943  (ftype != FT_LONG && num_vect & 1 ) ||
944  i == line_len[1]) {
945  shift = 0;
946  } else if (ftype == FT_LONG) {
947  shift = i;
948  } else
949  shift = i*i;
950 
951  for (j = 0; j < num_vect && (j+num_vect*i < block_size*num_blocks); j++)
952  tab[i*num_vect+j] = i*num_vect + (j + shift) % num_vect;
953  }
954 }
955 
956 /**
957  * Interpret the input data as in the following table:
958  *
959  * @verbatim
960  *
961  * abcdefgh
962  * ijklmnop
963  * qrstuvw
964  * x123456
965  *
966  * @endverbatim
967  *
968  * and transpose it, giving the output
969  * aiqxbjr1cks2dlt3emu4fvn5gow6hp
970  */
971 static void transpose_perm(int16_t *out, int16_t *in, int num_vect,
972  const uint8_t line_len[2], int length_div)
973 {
974  int i,j;
975  int cont= 0;
976  for (i = 0; i < num_vect; i++)
977  for (j = 0; j < line_len[i >= length_div]; j++)
978  out[cont++] = in[j*num_vect + i];
979 }
980 
981 static void linear_perm(int16_t *out, int16_t *in, int n_blocks, int size)
982 {
983  int block_size = size/n_blocks;
984  int i;
985 
986  for (i = 0; i < size; i++)
987  out[i] = block_size * (in[i] % n_blocks) + in[i] / n_blocks;
988 }
989 
990 static av_cold void construct_perm_table(TwinContext *tctx,enum FrameType ftype)
991 {
992  int block_size;
993  const ModeTab *mtab = tctx->mtab;
994  int size;
995  int16_t *tmp_perm = (int16_t *) tctx->tmp_buf;
996 
997  if (ftype == FT_PPC) {
998  size = tctx->avctx->channels;
999  block_size = mtab->ppc_shape_len;
1000  } else {
1001  size = tctx->avctx->channels * mtab->fmode[ftype].sub;
1002  block_size = mtab->size / mtab->fmode[ftype].sub;
1003  }
1004 
1005  permutate_in_line(tmp_perm, tctx->n_div[ftype], size,
1006  block_size, tctx->length[ftype],
1007  tctx->length_change[ftype], ftype);
1008 
1009  transpose_perm(tctx->permut[ftype], tmp_perm, tctx->n_div[ftype],
1010  tctx->length[ftype], tctx->length_change[ftype]);
1011 
1012  linear_perm(tctx->permut[ftype], tctx->permut[ftype], size,
1013  size*block_size);
1014 }
1015 
1017 {
1018  const ModeTab *mtab = tctx->mtab;
1019  int n_ch = tctx->avctx->channels;
1020  int total_fr_bits = tctx->avctx->bit_rate*mtab->size/
1021  tctx->avctx->sample_rate;
1022 
1023  int lsp_bits_per_block = n_ch*(mtab->lsp_bit0 + mtab->lsp_bit1 +
1024  mtab->lsp_split*mtab->lsp_bit2);
1025 
1026  int ppc_bits = n_ch*(mtab->pgain_bit + mtab->ppc_shape_bit +
1027  mtab->ppc_period_bit);
1028 
1029  int bsize_no_main_cb[3];
1030  int bse_bits[3];
1031  int i;
1032  enum FrameType frametype;
1033 
1034  for (i = 0; i < 3; i++)
1035  // +1 for history usage switch
1036  bse_bits[i] = n_ch *
1037  (mtab->fmode[i].bark_n_coef * mtab->fmode[i].bark_n_bit + 1);
1038 
1039  bsize_no_main_cb[2] = bse_bits[2] + lsp_bits_per_block + ppc_bits +
1040  WINDOW_TYPE_BITS + n_ch*GAIN_BITS;
1041 
1042  for (i = 0; i < 2; i++)
1043  bsize_no_main_cb[i] =
1044  lsp_bits_per_block + n_ch*GAIN_BITS + WINDOW_TYPE_BITS +
1045  mtab->fmode[i].sub*(bse_bits[i] + n_ch*SUB_GAIN_BITS);
1046 
1047  // The remaining bits are all used for the main spectrum coefficients
1048  for (i = 0; i < 4; i++) {
1049  int bit_size;
1050  int vect_size;
1051  int rounded_up, rounded_down, num_rounded_down, num_rounded_up;
1052  if (i == 3) {
1053  bit_size = n_ch * mtab->ppc_shape_bit;
1054  vect_size = n_ch * mtab->ppc_shape_len;
1055  } else {
1056  bit_size = total_fr_bits - bsize_no_main_cb[i];
1057  vect_size = n_ch * mtab->size;
1058  }
1059 
1060  tctx->n_div[i] = (bit_size + 13) / 14;
1061 
1062  rounded_up = (bit_size + tctx->n_div[i] - 1)/tctx->n_div[i];
1063  rounded_down = (bit_size )/tctx->n_div[i];
1064  num_rounded_down = rounded_up * tctx->n_div[i] - bit_size;
1065  num_rounded_up = tctx->n_div[i] - num_rounded_down;
1066  tctx->bits_main_spec[0][i][0] = (rounded_up + 1)/2;
1067  tctx->bits_main_spec[1][i][0] = (rounded_up )/2;
1068  tctx->bits_main_spec[0][i][1] = (rounded_down + 1)/2;
1069  tctx->bits_main_spec[1][i][1] = (rounded_down )/2;
1070  tctx->bits_main_spec_change[i] = num_rounded_up;
1071 
1072  rounded_up = (vect_size + tctx->n_div[i] - 1)/tctx->n_div[i];
1073  rounded_down = (vect_size )/tctx->n_div[i];
1074  num_rounded_down = rounded_up * tctx->n_div[i] - vect_size;
1075  num_rounded_up = tctx->n_div[i] - num_rounded_down;
1076  tctx->length[i][0] = rounded_up;
1077  tctx->length[i][1] = rounded_down;
1078  tctx->length_change[i] = num_rounded_up;
1079  }
1080 
1081  for (frametype = FT_SHORT; frametype <= FT_PPC; frametype++)
1082  construct_perm_table(tctx, frametype);
1083 }
1084 
1086 {
1087  TwinContext *tctx = avctx->priv_data;
1088  int i;
1089 
1090  for (i = 0; i < 3; i++) {
1091  ff_mdct_end(&tctx->mdct_ctx[i]);
1092  av_free(tctx->cos_tabs[i]);
1093  }
1094 
1095 
1096  av_free(tctx->curr_frame);
1097  av_free(tctx->spectrum);
1098  av_free(tctx->prev_frame);
1099  av_free(tctx->tmp_buf);
1100 
1101  return 0;
1102 }
1103 
1105 {
1106  int ret;
1107  TwinContext *tctx = avctx->priv_data;
1108  int isampf, ibps;
1109 
1110  tctx->avctx = avctx;
1111  avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
1112 
1113  if (!avctx->extradata || avctx->extradata_size < 12) {
1114  av_log(avctx, AV_LOG_ERROR, "Missing or incomplete extradata\n");
1115  return AVERROR_INVALIDDATA;
1116  }
1117  avctx->channels = AV_RB32(avctx->extradata ) + 1;
1118  avctx->bit_rate = AV_RB32(avctx->extradata + 4) * 1000;
1119  isampf = AV_RB32(avctx->extradata + 8);
1120 
1121  if (isampf < 8 || isampf > 44) {
1122  av_log(avctx, AV_LOG_ERROR, "Unsupported sample rate\n");
1123  return AVERROR_INVALIDDATA;
1124  }
1125  switch (isampf) {
1126  case 44: avctx->sample_rate = 44100; break;
1127  case 22: avctx->sample_rate = 22050; break;
1128  case 11: avctx->sample_rate = 11025; break;
1129  default: avctx->sample_rate = isampf * 1000; break;
1130  }
1131 
1132  if (avctx->channels <= 0 || avctx->channels > CHANNELS_MAX) {
1133  av_log(avctx, AV_LOG_ERROR, "Unsupported number of channels: %i\n",
1134  avctx->channels);
1135  return -1;
1136  }
1137  avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO :
1139 
1140  ibps = avctx->bit_rate / (1000 * avctx->channels);
1141 
1142  if (ibps > 255U) {
1143  av_log(avctx, AV_LOG_ERROR, "unsupported per channel bitrate %dkbps\n", ibps);
1144  return AVERROR_INVALIDDATA;
1145  }
1146 
1147  switch ((isampf << 8) + ibps) {
1148  case (8 <<8) + 8: tctx->mtab = &mode_08_08; break;
1149  case (11<<8) + 8: tctx->mtab = &mode_11_08; break;
1150  case (11<<8) + 10: tctx->mtab = &mode_11_10; break;
1151  case (16<<8) + 16: tctx->mtab = &mode_16_16; break;
1152  case (22<<8) + 20: tctx->mtab = &mode_22_20; break;
1153  case (22<<8) + 24: tctx->mtab = &mode_22_24; break;
1154  case (22<<8) + 32: tctx->mtab = &mode_22_32; break;
1155  case (44<<8) + 40: tctx->mtab = &mode_44_40; break;
1156  case (44<<8) + 48: tctx->mtab = &mode_44_48; break;
1157  default:
1158  av_log(avctx, AV_LOG_ERROR, "This version does not support %d kHz - %d kbit/s/ch mode.\n", isampf, isampf);
1159  return -1;
1160  }
1161 
1163  if ((ret = init_mdct_win(tctx))) {
1164  av_log(avctx, AV_LOG_ERROR, "Error initializing MDCT\n");
1165  twin_decode_close(avctx);
1166  return ret;
1167  }
1168  init_bitstream_params(tctx);
1169 
1170  memset_float(tctx->bark_hist[0][0], 0.1, FF_ARRAY_ELEMS(tctx->bark_hist));
1171 
1172  return 0;
1173 }
1174 
1176  .name = "twinvq",
1177  .type = AVMEDIA_TYPE_AUDIO,
1178  .id = AV_CODEC_ID_TWINVQ,
1179  .priv_data_size = sizeof(TwinContext),
1183  .capabilities = CODEC_CAP_DR1,
1184  .long_name = NULL_IF_CONFIG_SMALL("VQF TwinVQ"),
1185  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
1187 };