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twinvqdec.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 "avcodec.h"
27 #include "get_bits.h"
28 #include "internal.h"
29 #include "twinvq.h"
30 #include "twinvq_data.h"
31 
32 static const TwinVQModeTab mode_08_08 = {
33  {
34  { 8, bark_tab_s08_64, 10, tab.fcb08s, 1, 5, tab.cb0808s0, tab.cb0808s1, 18 },
35  { 2, bark_tab_m08_256, 20, tab.fcb08m, 2, 5, tab.cb0808m0, tab.cb0808m1, 16 },
36  { 1, bark_tab_l08_512, 30, tab.fcb08l, 3, 6, tab.cb0808l0, tab.cb0808l1, 17 }
37  },
38  512, 12, tab.lsp08, 1, 5, 3, 3, tab.shape08, 8, 28, 20, 6, 40
39 };
40 
41 static const TwinVQModeTab mode_11_08 = {
42  {
43  { 8, bark_tab_s11_64, 10, tab.fcb11s, 1, 5, tab.cb1108s0, tab.cb1108s1, 29 },
44  { 2, bark_tab_m11_256, 20, tab.fcb11m, 2, 5, tab.cb1108m0, tab.cb1108m1, 24 },
45  { 1, bark_tab_l11_512, 30, tab.fcb11l, 3, 6, tab.cb1108l0, tab.cb1108l1, 27 }
46  },
47  512, 16, tab.lsp11, 1, 6, 4, 3, tab.shape11, 9, 36, 30, 7, 90
48 };
49 
50 static const TwinVQModeTab mode_11_10 = {
51  {
52  { 8, bark_tab_s11_64, 10, tab.fcb11s, 1, 5, tab.cb1110s0, tab.cb1110s1, 21 },
53  { 2, bark_tab_m11_256, 20, tab.fcb11m, 2, 5, tab.cb1110m0, tab.cb1110m1, 18 },
54  { 1, bark_tab_l11_512, 30, tab.fcb11l, 3, 6, tab.cb1110l0, tab.cb1110l1, 20 }
55  },
56  512, 16, tab.lsp11, 1, 6, 4, 3, tab.shape11, 9, 36, 30, 7, 90
57 };
58 
59 static const TwinVQModeTab mode_16_16 = {
60  {
61  { 8, bark_tab_s16_128, 10, tab.fcb16s, 1, 5, tab.cb1616s0, tab.cb1616s1, 16 },
62  { 2, bark_tab_m16_512, 20, tab.fcb16m, 2, 5, tab.cb1616m0, tab.cb1616m1, 15 },
63  { 1, bark_tab_l16_1024, 30, tab.fcb16l, 3, 6, tab.cb1616l0, tab.cb1616l1, 16 }
64  },
65  1024, 16, tab.lsp16, 1, 6, 4, 3, tab.shape16, 9, 56, 60, 7, 180
66 };
67 
68 static const TwinVQModeTab mode_22_20 = {
69  {
70  { 8, bark_tab_s22_128, 10, tab.fcb22s_1, 1, 6, tab.cb2220s0, tab.cb2220s1, 18 },
71  { 2, bark_tab_m22_512, 20, tab.fcb22m_1, 2, 6, tab.cb2220m0, tab.cb2220m1, 17 },
72  { 1, bark_tab_l22_1024, 32, tab.fcb22l_1, 4, 6, tab.cb2220l0, tab.cb2220l1, 18 }
73  },
74  1024, 16, tab.lsp22_1, 1, 6, 4, 3, tab.shape22_1, 9, 56, 36, 7, 144
75 };
76 
77 static const TwinVQModeTab mode_22_24 = {
78  {
79  { 8, bark_tab_s22_128, 10, tab.fcb22s_1, 1, 6, tab.cb2224s0, tab.cb2224s1, 15 },
80  { 2, bark_tab_m22_512, 20, tab.fcb22m_1, 2, 6, tab.cb2224m0, tab.cb2224m1, 14 },
81  { 1, bark_tab_l22_1024, 32, tab.fcb22l_1, 4, 6, tab.cb2224l0, tab.cb2224l1, 15 }
82  },
83  1024, 16, tab.lsp22_1, 1, 6, 4, 3, tab.shape22_1, 9, 56, 36, 7, 144
84 };
85 
86 static const TwinVQModeTab mode_22_32 = {
87  {
88  { 4, bark_tab_s22_128, 10, tab.fcb22s_2, 1, 6, tab.cb2232s0, tab.cb2232s1, 11 },
89  { 2, bark_tab_m22_256, 20, tab.fcb22m_2, 2, 6, tab.cb2232m0, tab.cb2232m1, 11 },
90  { 1, bark_tab_l22_512, 32, tab.fcb22l_2, 4, 6, tab.cb2232l0, tab.cb2232l1, 12 }
91  },
92  512, 16, tab.lsp22_2, 1, 6, 4, 4, tab.shape22_2, 9, 56, 36, 7, 72
93 };
94 
95 static const TwinVQModeTab mode_44_40 = {
96  {
97  { 16, bark_tab_s44_128, 10, tab.fcb44s, 1, 6, tab.cb4440s0, tab.cb4440s1, 18 },
98  { 4, bark_tab_m44_512, 20, tab.fcb44m, 2, 6, tab.cb4440m0, tab.cb4440m1, 17 },
99  { 1, bark_tab_l44_2048, 40, tab.fcb44l, 4, 6, tab.cb4440l0, tab.cb4440l1, 17 }
100  },
101  2048, 20, tab.lsp44, 1, 6, 4, 4, tab.shape44, 9, 84, 54, 7, 432
102 };
103 
104 static const TwinVQModeTab mode_44_48 = {
105  {
106  { 16, bark_tab_s44_128, 10, tab.fcb44s, 1, 6, tab.cb4448s0, tab.cb4448s1, 15 },
107  { 4, bark_tab_m44_512, 20, tab.fcb44m, 2, 6, tab.cb4448m0, tab.cb4448m1, 14 },
108  { 1, bark_tab_l44_2048, 40, tab.fcb44l, 4, 6, tab.cb4448l0, tab.cb4448l1, 14 }
109  },
110  2048, 20, tab.lsp44, 1, 6, 4, 4, tab.shape44, 9, 84, 54, 7, 432
111 };
112 
113 /**
114  * Evaluate a * b / 400 rounded to the nearest integer. When, for example,
115  * a * b == 200 and the nearest integer is ill-defined, use a table to emulate
116  * the following broken float-based implementation used by the binary decoder:
117  *
118  * @code
119  * static int very_broken_op(int a, int b)
120  * {
121  * static float test; // Ugh, force gcc to do the division first...
122  *
123  * test = a / 400.0;
124  * return b * test + 0.5;
125  * }
126  * @endcode
127  *
128  * @note if this function is replaced by just ROUNDED_DIV(a * b, 400.0), the
129  * stddev between the original file (before encoding with Yamaha encoder) and
130  * the decoded output increases, which leads one to believe that the encoder
131  * expects exactly this broken calculation.
132  */
133 static int very_broken_op(int a, int b)
134 {
135  int x = a * b + 200;
136  int size;
137  const uint8_t *rtab;
138 
139  if (x % 400 || b % 5)
140  return x / 400;
141 
142  x /= 400;
143 
144  size = tabs[b / 5].size;
145  rtab = tabs[b / 5].tab;
146  return x - rtab[size * av_log2(2 * (x - 1) / size) + (x - 1) % size];
147 }
148 
149 /**
150  * Sum to data a periodic peak of a given period, width and shape.
151  *
152  * @param period the period of the peak divised by 400.0
153  */
154 static void add_peak(int period, int width, const float *shape,
155  float ppc_gain, float *speech, int len)
156 {
157  int i, j;
158 
159  const float *shape_end = shape + len;
160  int center;
161 
162  // First peak centered around zero
163  for (i = 0; i < width / 2; i++)
164  speech[i] += ppc_gain * *shape++;
165 
166  for (i = 1; i < ROUNDED_DIV(len, width); i++) {
167  center = very_broken_op(period, i);
168  for (j = -width / 2; j < (width + 1) / 2; j++)
169  speech[j + center] += ppc_gain * *shape++;
170  }
171 
172  // For the last block, be careful not to go beyond the end of the buffer
173  center = very_broken_op(period, i);
174  for (j = -width / 2; j < (width + 1) / 2 && shape < shape_end; j++)
175  speech[j + center] += ppc_gain * *shape++;
176 }
177 
178 static void decode_ppc(TwinVQContext *tctx, int period_coef, int g_coef,
179  const float *shape, float *speech)
180 {
181  const TwinVQModeTab *mtab = tctx->mtab;
182  int isampf = tctx->avctx->sample_rate / 1000;
183  int ibps = tctx->avctx->bit_rate / (1000 * tctx->avctx->channels);
184  int min_period = ROUNDED_DIV(40 * 2 * mtab->size, isampf);
185  int max_period = ROUNDED_DIV(40 * 2 * mtab->size * 6, isampf);
186  int period_range = max_period - min_period;
187  float pgain_step = 25000.0 / ((1 << mtab->pgain_bit) - 1);
188  float ppc_gain = 1.0 / 8192 *
189  twinvq_mulawinv(pgain_step * g_coef +
190  pgain_step / 2,
191  25000.0, TWINVQ_PGAIN_MU);
192 
193  // This is actually the period multiplied by 400. It is just linearly coded
194  // between its maximum and minimum value.
195  int period = min_period +
196  ROUNDED_DIV(period_coef * period_range,
197  (1 << mtab->ppc_period_bit) - 1);
198  int width;
199 
200  if (isampf == 22 && ibps == 32) {
201  // For some unknown reason, NTT decided to code this case differently...
202  width = ROUNDED_DIV((period + 800) * mtab->peak_per2wid,
203  400 * mtab->size);
204  } else
205  width = period * mtab->peak_per2wid / (400 * mtab->size);
206 
207  add_peak(period, width, shape, ppc_gain, speech, mtab->ppc_shape_len);
208 }
209 
210 static void dec_bark_env(TwinVQContext *tctx, const uint8_t *in, int use_hist,
211  int ch, float *out, float gain,
212  enum TwinVQFrameType ftype)
213 {
214  const TwinVQModeTab *mtab = tctx->mtab;
215  int i, j;
216  float *hist = tctx->bark_hist[ftype][ch];
217  float val = ((const float []) { 0.4, 0.35, 0.28 })[ftype];
218  int bark_n_coef = mtab->fmode[ftype].bark_n_coef;
219  int fw_cb_len = mtab->fmode[ftype].bark_env_size / bark_n_coef;
220  int idx = 0;
221 
222  for (i = 0; i < fw_cb_len; i++)
223  for (j = 0; j < bark_n_coef; j++, idx++) {
224  float tmp2 = mtab->fmode[ftype].bark_cb[fw_cb_len * in[j] + i] *
225  (1.0 / 4096);
226  float st = use_hist ? (1.0 - val) * tmp2 + val * hist[idx] + 1.0
227  : tmp2 + 1.0;
228 
229  hist[idx] = tmp2;
230  if (st < -1.0)
231  st = 1.0;
232 
233  twinvq_memset_float(out, st * gain, mtab->fmode[ftype].bark_tab[idx]);
234  out += mtab->fmode[ftype].bark_tab[idx];
235  }
236 }
237 
238 static void read_cb_data(TwinVQContext *tctx, GetBitContext *gb,
239  uint8_t *dst, enum TwinVQFrameType ftype)
240 {
241  int i;
242 
243  for (i = 0; i < tctx->n_div[ftype]; i++) {
244  int bs_second_part = (i >= tctx->bits_main_spec_change[ftype]);
245 
246  *dst++ = get_bits(gb, tctx->bits_main_spec[0][ftype][bs_second_part]);
247  *dst++ = get_bits(gb, tctx->bits_main_spec[1][ftype][bs_second_part]);
248  }
249 }
250 
252  const uint8_t *buf, int buf_size)
253 {
254  TwinVQFrameData *bits = &tctx->bits;
255  const TwinVQModeTab *mtab = tctx->mtab;
256  int channels = tctx->avctx->channels;
257  int sub;
258  GetBitContext gb;
259  int i, j, k;
260 
261  init_get_bits(&gb, buf, buf_size * 8);
262  skip_bits(&gb, get_bits(&gb, 8));
263 
265 
266  if (bits->window_type > 8) {
267  av_log(avctx, AV_LOG_ERROR, "Invalid window type, broken sample?\n");
268  return AVERROR_INVALIDDATA;
269  }
270 
272 
273  sub = mtab->fmode[bits->ftype].sub;
274 
275  read_cb_data(tctx, &gb, bits->main_coeffs, bits->ftype);
276 
277  for (i = 0; i < channels; i++)
278  for (j = 0; j < sub; j++)
279  for (k = 0; k < mtab->fmode[bits->ftype].bark_n_coef; k++)
280  bits->bark1[i][j][k] =
281  get_bits(&gb, mtab->fmode[bits->ftype].bark_n_bit);
282 
283  for (i = 0; i < channels; i++)
284  for (j = 0; j < sub; j++)
285  bits->bark_use_hist[i][j] = get_bits1(&gb);
286 
287  if (bits->ftype == TWINVQ_FT_LONG) {
288  for (i = 0; i < channels; i++)
289  bits->gain_bits[i] = get_bits(&gb, TWINVQ_GAIN_BITS);
290  } else {
291  for (i = 0; i < channels; i++) {
292  bits->gain_bits[i] = get_bits(&gb, TWINVQ_GAIN_BITS);
293  for (j = 0; j < sub; j++)
294  bits->sub_gain_bits[i * sub + j] = get_bits(&gb,
296  }
297  }
298 
299  for (i = 0; i < channels; i++) {
300  bits->lpc_hist_idx[i] = get_bits(&gb, mtab->lsp_bit0);
301  bits->lpc_idx1[i] = get_bits(&gb, mtab->lsp_bit1);
302 
303  for (j = 0; j < mtab->lsp_split; j++)
304  bits->lpc_idx2[i][j] = get_bits(&gb, mtab->lsp_bit2);
305  }
306 
307  if (bits->ftype == TWINVQ_FT_LONG) {
308  read_cb_data(tctx, &gb, bits->ppc_coeffs, 3);
309  for (i = 0; i < channels; i++) {
310  bits->p_coef[i] = get_bits(&gb, mtab->ppc_period_bit);
311  bits->g_coef[i] = get_bits(&gb, mtab->pgain_bit);
312  }
313  }
314 
315  return (get_bits_count(&gb) + 7) / 8;
316 }
317 
319 {
320  int isampf, ibps;
321  TwinVQContext *tctx = avctx->priv_data;
322 
323  if (!avctx->extradata || avctx->extradata_size < 12) {
324  av_log(avctx, AV_LOG_ERROR, "Missing or incomplete extradata\n");
325  return AVERROR_INVALIDDATA;
326  }
327  avctx->channels = AV_RB32(avctx->extradata) + 1;
328  avctx->bit_rate = AV_RB32(avctx->extradata + 4) * 1000;
329  isampf = AV_RB32(avctx->extradata + 8);
330 
331  if (isampf < 8 || isampf > 44) {
332  av_log(avctx, AV_LOG_ERROR, "Unsupported sample rate\n");
333  return AVERROR_INVALIDDATA;
334  }
335  switch (isampf) {
336  case 44:
337  avctx->sample_rate = 44100;
338  break;
339  case 22:
340  avctx->sample_rate = 22050;
341  break;
342  case 11:
343  avctx->sample_rate = 11025;
344  break;
345  default:
346  avctx->sample_rate = isampf * 1000;
347  break;
348  }
349 
350  if (avctx->channels <= 0 || avctx->channels > TWINVQ_CHANNELS_MAX) {
351  av_log(avctx, AV_LOG_ERROR, "Unsupported number of channels: %i\n",
352  avctx->channels);
353  return -1;
354  }
355  avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO
357 
358  ibps = avctx->bit_rate / (1000 * avctx->channels);
359  if (ibps < 8 || ibps > 48) {
360  av_log(avctx, AV_LOG_ERROR, "Bad bitrate per channel value %d\n", ibps);
361  return AVERROR_INVALIDDATA;
362  }
363 
364  switch ((isampf << 8) + ibps) {
365  case (8 << 8) + 8:
366  tctx->mtab = &mode_08_08;
367  break;
368  case (11 << 8) + 8:
369  tctx->mtab = &mode_11_08;
370  break;
371  case (11 << 8) + 10:
372  tctx->mtab = &mode_11_10;
373  break;
374  case (16 << 8) + 16:
375  tctx->mtab = &mode_16_16;
376  break;
377  case (22 << 8) + 20:
378  tctx->mtab = &mode_22_20;
379  break;
380  case (22 << 8) + 24:
381  tctx->mtab = &mode_22_24;
382  break;
383  case (22 << 8) + 32:
384  tctx->mtab = &mode_22_32;
385  break;
386  case (44 << 8) + 40:
387  tctx->mtab = &mode_44_40;
388  break;
389  case (44 << 8) + 48:
390  tctx->mtab = &mode_44_48;
391  break;
392  default:
393  av_log(avctx, AV_LOG_ERROR,
394  "This version does not support %d kHz - %d kbit/s/ch mode.\n",
395  isampf, isampf);
396  return -1;
397  }
398 
399  avctx->block_align = (avctx->bit_rate * tctx->mtab->size
400  / avctx->sample_rate + 15) / 8;
401 
402  tctx->codec = TWINVQ_CODEC_VQF;
404  tctx->dec_bark_env = dec_bark_env;
405  tctx->decode_ppc = decode_ppc;
406 
407  return ff_twinvq_decode_init(avctx);
408 }
409 
411  .name = "twinvq",
412  .long_name = NULL_IF_CONFIG_SMALL("VQF TwinVQ"),
413  .type = AVMEDIA_TYPE_AUDIO,
414  .id = AV_CODEC_ID_TWINVQ,
415  .priv_data_size = sizeof(TwinVQContext),
419  .capabilities = CODEC_CAP_DR1,
420  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
422 };