wmadec.c
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1 /*
2  * WMA compatible decoder
3  * Copyright (c) 2002 The Libav Project
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
36 #include "avcodec.h"
37 #include "wma.h"
38 
39 #undef NDEBUG
40 #include <assert.h>
41 
42 #define EXPVLCBITS 8
43 #define EXPMAX ((19+EXPVLCBITS-1)/EXPVLCBITS)
44 
45 #define HGAINVLCBITS 9
46 #define HGAINMAX ((13+HGAINVLCBITS-1)/HGAINVLCBITS)
47 
48 static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len);
49 
50 #ifdef TRACE
51 static void dump_shorts(WMACodecContext *s, const char *name, const short *tab, int n)
52 {
53  int i;
54 
55  tprintf(s->avctx, "%s[%d]:\n", name, n);
56  for(i=0;i<n;i++) {
57  if ((i & 7) == 0)
58  tprintf(s->avctx, "%4d: ", i);
59  tprintf(s->avctx, " %5d.0", tab[i]);
60  if ((i & 7) == 7)
61  tprintf(s->avctx, "\n");
62  }
63 }
64 
65 static void dump_floats(WMACodecContext *s, const char *name, int prec, const float *tab, int n)
66 {
67  int i;
68 
69  tprintf(s->avctx, "%s[%d]:\n", name, n);
70  for(i=0;i<n;i++) {
71  if ((i & 7) == 0)
72  tprintf(s->avctx, "%4d: ", i);
73  tprintf(s->avctx, " %8.*f", prec, tab[i]);
74  if ((i & 7) == 7)
75  tprintf(s->avctx, "\n");
76  }
77  if ((i & 7) != 0)
78  tprintf(s->avctx, "\n");
79 }
80 #endif
81 
82 static int wma_decode_init(AVCodecContext * avctx)
83 {
84  WMACodecContext *s = avctx->priv_data;
85  int i, flags2;
86  uint8_t *extradata;
87 
88  s->avctx = avctx;
89 
90  /* extract flag infos */
91  flags2 = 0;
92  extradata = avctx->extradata;
93  if (avctx->codec->id == CODEC_ID_WMAV1 && avctx->extradata_size >= 4) {
94  flags2 = AV_RL16(extradata+2);
95  } else if (avctx->codec->id == CODEC_ID_WMAV2 && avctx->extradata_size >= 6) {
96  flags2 = AV_RL16(extradata+4);
97  }
98 // for(i=0; i<avctx->extradata_size; i++)
99 // av_log(NULL, AV_LOG_ERROR, "%02X ", extradata[i]);
100 
101  s->use_exp_vlc = flags2 & 0x0001;
102  s->use_bit_reservoir = flags2 & 0x0002;
103  s->use_variable_block_len = flags2 & 0x0004;
104 
105  if(ff_wma_init(avctx, flags2)<0)
106  return -1;
107 
108  /* init MDCT */
109  for(i = 0; i < s->nb_block_sizes; i++)
110  ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1, 1.0);
111 
112  if (s->use_noise_coding) {
114  ff_wma_hgain_huffbits, 1, 1,
115  ff_wma_hgain_huffcodes, 2, 2, 0);
116  }
117 
118  if (s->use_exp_vlc) {
119  init_vlc(&s->exp_vlc, EXPVLCBITS, sizeof(ff_aac_scalefactor_bits), //FIXME move out of context
121  ff_aac_scalefactor_code, 4, 4, 0);
122  } else {
124  }
125 
126  avctx->sample_fmt = AV_SAMPLE_FMT_S16;
127 
129  avctx->coded_frame = &s->frame;
130 
131  return 0;
132 }
133 
140 static inline float pow_m1_4(WMACodecContext *s, float x)
141 {
142  union {
143  float f;
144  unsigned int v;
145  } u, t;
146  unsigned int e, m;
147  float a, b;
148 
149  u.f = x;
150  e = u.v >> 23;
151  m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
152  /* build interpolation scale: 1 <= t < 2. */
153  t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
154  a = s->lsp_pow_m_table1[m];
155  b = s->lsp_pow_m_table2[m];
156  return s->lsp_pow_e_table[e] * (a + b * t.f);
157 }
158 
159 static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len)
160 {
161  float wdel, a, b;
162  int i, e, m;
163 
164  wdel = M_PI / frame_len;
165  for(i=0;i<frame_len;i++)
166  s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
167 
168  /* tables for x^-0.25 computation */
169  for(i=0;i<256;i++) {
170  e = i - 126;
171  s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
172  }
173 
174  /* NOTE: these two tables are needed to avoid two operations in
175  pow_m1_4 */
176  b = 1.0;
177  for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--) {
178  m = (1 << LSP_POW_BITS) + i;
179  a = (float)m * (0.5 / (1 << LSP_POW_BITS));
180  a = pow(a, -0.25);
181  s->lsp_pow_m_table1[i] = 2 * a - b;
182  s->lsp_pow_m_table2[i] = b - a;
183  b = a;
184  }
185 }
186 
192  float *out, float *val_max_ptr,
193  int n, float *lsp)
194 {
195  int i, j;
196  float p, q, w, v, val_max;
197 
198  val_max = 0;
199  for(i=0;i<n;i++) {
200  p = 0.5f;
201  q = 0.5f;
202  w = s->lsp_cos_table[i];
203  for(j=1;j<NB_LSP_COEFS;j+=2){
204  q *= w - lsp[j - 1];
205  p *= w - lsp[j];
206  }
207  p *= p * (2.0f - w);
208  q *= q * (2.0f + w);
209  v = p + q;
210  v = pow_m1_4(s, v);
211  if (v > val_max)
212  val_max = v;
213  out[i] = v;
214  }
215  *val_max_ptr = val_max;
216 }
217 
221 static void decode_exp_lsp(WMACodecContext *s, int ch)
222 {
223  float lsp_coefs[NB_LSP_COEFS];
224  int val, i;
225 
226  for(i = 0; i < NB_LSP_COEFS; i++) {
227  if (i == 0 || i >= 8)
228  val = get_bits(&s->gb, 3);
229  else
230  val = get_bits(&s->gb, 4);
231  lsp_coefs[i] = ff_wma_lsp_codebook[i][val];
232  }
233 
234  wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
235  s->block_len, lsp_coefs);
236 }
237 
239 static const float pow_tab[] = {
240  1.7782794100389e-04, 2.0535250264571e-04,
241  2.3713737056617e-04, 2.7384196342644e-04,
242  3.1622776601684e-04, 3.6517412725484e-04,
243  4.2169650342858e-04, 4.8696752516586e-04,
244  5.6234132519035e-04, 6.4938163157621e-04,
245  7.4989420933246e-04, 8.6596432336006e-04,
246  1.0000000000000e-03, 1.1547819846895e-03,
247  1.3335214321633e-03, 1.5399265260595e-03,
248  1.7782794100389e-03, 2.0535250264571e-03,
249  2.3713737056617e-03, 2.7384196342644e-03,
250  3.1622776601684e-03, 3.6517412725484e-03,
251  4.2169650342858e-03, 4.8696752516586e-03,
252  5.6234132519035e-03, 6.4938163157621e-03,
253  7.4989420933246e-03, 8.6596432336006e-03,
254  1.0000000000000e-02, 1.1547819846895e-02,
255  1.3335214321633e-02, 1.5399265260595e-02,
256  1.7782794100389e-02, 2.0535250264571e-02,
257  2.3713737056617e-02, 2.7384196342644e-02,
258  3.1622776601684e-02, 3.6517412725484e-02,
259  4.2169650342858e-02, 4.8696752516586e-02,
260  5.6234132519035e-02, 6.4938163157621e-02,
261  7.4989420933246e-02, 8.6596432336007e-02,
262  1.0000000000000e-01, 1.1547819846895e-01,
263  1.3335214321633e-01, 1.5399265260595e-01,
264  1.7782794100389e-01, 2.0535250264571e-01,
265  2.3713737056617e-01, 2.7384196342644e-01,
266  3.1622776601684e-01, 3.6517412725484e-01,
267  4.2169650342858e-01, 4.8696752516586e-01,
268  5.6234132519035e-01, 6.4938163157621e-01,
269  7.4989420933246e-01, 8.6596432336007e-01,
270  1.0000000000000e+00, 1.1547819846895e+00,
271  1.3335214321633e+00, 1.5399265260595e+00,
272  1.7782794100389e+00, 2.0535250264571e+00,
273  2.3713737056617e+00, 2.7384196342644e+00,
274  3.1622776601684e+00, 3.6517412725484e+00,
275  4.2169650342858e+00, 4.8696752516586e+00,
276  5.6234132519035e+00, 6.4938163157621e+00,
277  7.4989420933246e+00, 8.6596432336007e+00,
278  1.0000000000000e+01, 1.1547819846895e+01,
279  1.3335214321633e+01, 1.5399265260595e+01,
280  1.7782794100389e+01, 2.0535250264571e+01,
281  2.3713737056617e+01, 2.7384196342644e+01,
282  3.1622776601684e+01, 3.6517412725484e+01,
283  4.2169650342858e+01, 4.8696752516586e+01,
284  5.6234132519035e+01, 6.4938163157621e+01,
285  7.4989420933246e+01, 8.6596432336007e+01,
286  1.0000000000000e+02, 1.1547819846895e+02,
287  1.3335214321633e+02, 1.5399265260595e+02,
288  1.7782794100389e+02, 2.0535250264571e+02,
289  2.3713737056617e+02, 2.7384196342644e+02,
290  3.1622776601684e+02, 3.6517412725484e+02,
291  4.2169650342858e+02, 4.8696752516586e+02,
292  5.6234132519035e+02, 6.4938163157621e+02,
293  7.4989420933246e+02, 8.6596432336007e+02,
294  1.0000000000000e+03, 1.1547819846895e+03,
295  1.3335214321633e+03, 1.5399265260595e+03,
296  1.7782794100389e+03, 2.0535250264571e+03,
297  2.3713737056617e+03, 2.7384196342644e+03,
298  3.1622776601684e+03, 3.6517412725484e+03,
299  4.2169650342858e+03, 4.8696752516586e+03,
300  5.6234132519035e+03, 6.4938163157621e+03,
301  7.4989420933246e+03, 8.6596432336007e+03,
302  1.0000000000000e+04, 1.1547819846895e+04,
303  1.3335214321633e+04, 1.5399265260595e+04,
304  1.7782794100389e+04, 2.0535250264571e+04,
305  2.3713737056617e+04, 2.7384196342644e+04,
306  3.1622776601684e+04, 3.6517412725484e+04,
307  4.2169650342858e+04, 4.8696752516586e+04,
308  5.6234132519035e+04, 6.4938163157621e+04,
309  7.4989420933246e+04, 8.6596432336007e+04,
310  1.0000000000000e+05, 1.1547819846895e+05,
311  1.3335214321633e+05, 1.5399265260595e+05,
312  1.7782794100389e+05, 2.0535250264571e+05,
313  2.3713737056617e+05, 2.7384196342644e+05,
314  3.1622776601684e+05, 3.6517412725484e+05,
315  4.2169650342858e+05, 4.8696752516586e+05,
316  5.6234132519035e+05, 6.4938163157621e+05,
317  7.4989420933246e+05, 8.6596432336007e+05,
318 };
319 
323 static int decode_exp_vlc(WMACodecContext *s, int ch)
324 {
325  int last_exp, n, code;
326  const uint16_t *ptr;
327  float v, max_scale;
328  uint32_t *q, *q_end, iv;
329  const float *ptab = pow_tab + 60;
330  const uint32_t *iptab = (const uint32_t*)ptab;
331 
332  ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
333  q = (uint32_t *)s->exponents[ch];
334  q_end = q + s->block_len;
335  max_scale = 0;
336  if (s->version == 1) {
337  last_exp = get_bits(&s->gb, 5) + 10;
338  v = ptab[last_exp];
339  iv = iptab[last_exp];
340  max_scale = v;
341  n = *ptr++;
342  switch (n & 3) do {
343  case 0: *q++ = iv;
344  case 3: *q++ = iv;
345  case 2: *q++ = iv;
346  case 1: *q++ = iv;
347  } while ((n -= 4) > 0);
348  }else
349  last_exp = 36;
350 
351  while (q < q_end) {
352  code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX);
353  if (code < 0){
354  av_log(s->avctx, AV_LOG_ERROR, "Exponent vlc invalid\n");
355  return -1;
356  }
357  /* NOTE: this offset is the same as MPEG4 AAC ! */
358  last_exp += code - 60;
359  if ((unsigned)last_exp + 60 >= FF_ARRAY_ELEMS(pow_tab)) {
360  av_log(s->avctx, AV_LOG_ERROR, "Exponent out of range: %d\n",
361  last_exp);
362  return -1;
363  }
364  v = ptab[last_exp];
365  iv = iptab[last_exp];
366  if (v > max_scale)
367  max_scale = v;
368  n = *ptr++;
369  switch (n & 3) do {
370  case 0: *q++ = iv;
371  case 3: *q++ = iv;
372  case 2: *q++ = iv;
373  case 1: *q++ = iv;
374  } while ((n -= 4) > 0);
375  }
376  s->max_exponent[ch] = max_scale;
377  return 0;
378 }
379 
380 
387 static void wma_window(WMACodecContext *s, float *out)
388 {
389  float *in = s->output;
390  int block_len, bsize, n;
391 
392  /* left part */
393  if (s->block_len_bits <= s->prev_block_len_bits) {
394  block_len = s->block_len;
395  bsize = s->frame_len_bits - s->block_len_bits;
396 
397  s->dsp.vector_fmul_add(out, in, s->windows[bsize],
398  out, block_len);
399 
400  } else {
401  block_len = 1 << s->prev_block_len_bits;
402  n = (s->block_len - block_len) / 2;
403  bsize = s->frame_len_bits - s->prev_block_len_bits;
404 
405  s->dsp.vector_fmul_add(out+n, in+n, s->windows[bsize],
406  out+n, block_len);
407 
408  memcpy(out+n+block_len, in+n+block_len, n*sizeof(float));
409  }
410 
411  out += s->block_len;
412  in += s->block_len;
413 
414  /* right part */
415  if (s->block_len_bits <= s->next_block_len_bits) {
416  block_len = s->block_len;
417  bsize = s->frame_len_bits - s->block_len_bits;
418 
419  s->dsp.vector_fmul_reverse(out, in, s->windows[bsize], block_len);
420 
421  } else {
422  block_len = 1 << s->next_block_len_bits;
423  n = (s->block_len - block_len) / 2;
424  bsize = s->frame_len_bits - s->next_block_len_bits;
425 
426  memcpy(out, in, n*sizeof(float));
427 
428  s->dsp.vector_fmul_reverse(out+n, in+n, s->windows[bsize], block_len);
429 
430  memset(out+n+block_len, 0, n*sizeof(float));
431  }
432 }
433 
434 
440 {
441  int n, v, a, ch, bsize;
442  int coef_nb_bits, total_gain;
443  int nb_coefs[MAX_CHANNELS];
444  float mdct_norm;
445  FFTContext *mdct;
446 
447 #ifdef TRACE
448  tprintf(s->avctx, "***decode_block: %d:%d\n", s->frame_count - 1, s->block_num);
449 #endif
450 
451  /* compute current block length */
452  if (s->use_variable_block_len) {
453  n = av_log2(s->nb_block_sizes - 1) + 1;
454 
455  if (s->reset_block_lengths) {
456  s->reset_block_lengths = 0;
457  v = get_bits(&s->gb, n);
458  if (v >= s->nb_block_sizes){
459  av_log(s->avctx, AV_LOG_ERROR, "prev_block_len_bits %d out of range\n", s->frame_len_bits - v);
460  return -1;
461  }
463  v = get_bits(&s->gb, n);
464  if (v >= s->nb_block_sizes){
465  av_log(s->avctx, AV_LOG_ERROR, "block_len_bits %d out of range\n", s->frame_len_bits - v);
466  return -1;
467  }
468  s->block_len_bits = s->frame_len_bits - v;
469  } else {
470  /* update block lengths */
473  }
474  v = get_bits(&s->gb, n);
475  if (v >= s->nb_block_sizes){
476  av_log(s->avctx, AV_LOG_ERROR, "next_block_len_bits %d out of range\n", s->frame_len_bits - v);
477  return -1;
478  }
480  } else {
481  /* fixed block len */
485  }
486 
487  /* now check if the block length is coherent with the frame length */
488  s->block_len = 1 << s->block_len_bits;
489  if ((s->block_pos + s->block_len) > s->frame_len){
490  av_log(s->avctx, AV_LOG_ERROR, "frame_len overflow\n");
491  return -1;
492  }
493 
494  if (s->nb_channels == 2) {
495  s->ms_stereo = get_bits1(&s->gb);
496  }
497  v = 0;
498  for(ch = 0; ch < s->nb_channels; ch++) {
499  a = get_bits1(&s->gb);
500  s->channel_coded[ch] = a;
501  v |= a;
502  }
503 
504  bsize = s->frame_len_bits - s->block_len_bits;
505 
506  /* if no channel coded, no need to go further */
507  /* XXX: fix potential framing problems */
508  if (!v)
509  goto next;
510 
511  /* read total gain and extract corresponding number of bits for
512  coef escape coding */
513  total_gain = 1;
514  for(;;) {
515  a = get_bits(&s->gb, 7);
516  total_gain += a;
517  if (a != 127)
518  break;
519  }
520 
521  coef_nb_bits= ff_wma_total_gain_to_bits(total_gain);
522 
523  /* compute number of coefficients */
524  n = s->coefs_end[bsize] - s->coefs_start;
525  for(ch = 0; ch < s->nb_channels; ch++)
526  nb_coefs[ch] = n;
527 
528  /* complex coding */
529  if (s->use_noise_coding) {
530 
531  for(ch = 0; ch < s->nb_channels; ch++) {
532  if (s->channel_coded[ch]) {
533  int i, n, a;
534  n = s->exponent_high_sizes[bsize];
535  for(i=0;i<n;i++) {
536  a = get_bits1(&s->gb);
537  s->high_band_coded[ch][i] = a;
538  /* if noise coding, the coefficients are not transmitted */
539  if (a)
540  nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
541  }
542  }
543  }
544  for(ch = 0; ch < s->nb_channels; ch++) {
545  if (s->channel_coded[ch]) {
546  int i, n, val, code;
547 
548  n = s->exponent_high_sizes[bsize];
549  val = (int)0x80000000;
550  for(i=0;i<n;i++) {
551  if (s->high_band_coded[ch][i]) {
552  if (val == (int)0x80000000) {
553  val = get_bits(&s->gb, 7) - 19;
554  } else {
555  code = get_vlc2(&s->gb, s->hgain_vlc.table, HGAINVLCBITS, HGAINMAX);
556  if (code < 0){
557  av_log(s->avctx, AV_LOG_ERROR, "hgain vlc invalid\n");
558  return -1;
559  }
560  val += code - 18;
561  }
562  s->high_band_values[ch][i] = val;
563  }
564  }
565  }
566  }
567  }
568 
569  /* exponents can be reused in short blocks. */
570  if ((s->block_len_bits == s->frame_len_bits) ||
571  get_bits1(&s->gb)) {
572  for(ch = 0; ch < s->nb_channels; ch++) {
573  if (s->channel_coded[ch]) {
574  if (s->use_exp_vlc) {
575  if (decode_exp_vlc(s, ch) < 0)
576  return -1;
577  } else {
578  decode_exp_lsp(s, ch);
579  }
580  s->exponents_bsize[ch] = bsize;
581  }
582  }
583  }
584 
585  /* parse spectral coefficients : just RLE encoding */
586  for(ch = 0; ch < s->nb_channels; ch++) {
587  if (s->channel_coded[ch]) {
588  int tindex;
589  WMACoef* ptr = &s->coefs1[ch][0];
590 
591  /* special VLC tables are used for ms stereo because
592  there is potentially less energy there */
593  tindex = (ch == 1 && s->ms_stereo);
594  memset(ptr, 0, s->block_len * sizeof(WMACoef));
595  ff_wma_run_level_decode(s->avctx, &s->gb, &s->coef_vlc[tindex],
596  s->level_table[tindex], s->run_table[tindex],
597  0, ptr, 0, nb_coefs[ch],
598  s->block_len, s->frame_len_bits, coef_nb_bits);
599  }
600  if (s->version == 1 && s->nb_channels >= 2) {
601  align_get_bits(&s->gb);
602  }
603  }
604 
605  /* normalize */
606  {
607  int n4 = s->block_len / 2;
608  mdct_norm = 1.0 / (float)n4;
609  if (s->version == 1) {
610  mdct_norm *= sqrt(n4);
611  }
612  }
613 
614  /* finally compute the MDCT coefficients */
615  for(ch = 0; ch < s->nb_channels; ch++) {
616  if (s->channel_coded[ch]) {
617  WMACoef *coefs1;
618  float *coefs, *exponents, mult, mult1, noise;
619  int i, j, n, n1, last_high_band, esize;
620  float exp_power[HIGH_BAND_MAX_SIZE];
621 
622  coefs1 = s->coefs1[ch];
623  exponents = s->exponents[ch];
624  esize = s->exponents_bsize[ch];
625  mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
626  mult *= mdct_norm;
627  coefs = s->coefs[ch];
628  if (s->use_noise_coding) {
629  mult1 = mult;
630  /* very low freqs : noise */
631  for(i = 0;i < s->coefs_start; i++) {
632  *coefs++ = s->noise_table[s->noise_index] *
633  exponents[i<<bsize>>esize] * mult1;
634  s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
635  }
636 
637  n1 = s->exponent_high_sizes[bsize];
638 
639  /* compute power of high bands */
640  exponents = s->exponents[ch] +
641  (s->high_band_start[bsize]<<bsize>>esize);
642  last_high_band = 0; /* avoid warning */
643  for(j=0;j<n1;j++) {
645  s->block_len_bits][j];
646  if (s->high_band_coded[ch][j]) {
647  float e2, v;
648  e2 = 0;
649  for(i = 0;i < n; i++) {
650  v = exponents[i<<bsize>>esize];
651  e2 += v * v;
652  }
653  exp_power[j] = e2 / n;
654  last_high_band = j;
655  tprintf(s->avctx, "%d: power=%f (%d)\n", j, exp_power[j], n);
656  }
657  exponents += n<<bsize>>esize;
658  }
659 
660  /* main freqs and high freqs */
661  exponents = s->exponents[ch] + (s->coefs_start<<bsize>>esize);
662  for(j=-1;j<n1;j++) {
663  if (j < 0) {
664  n = s->high_band_start[bsize] -
665  s->coefs_start;
666  } else {
668  s->block_len_bits][j];
669  }
670  if (j >= 0 && s->high_band_coded[ch][j]) {
671  /* use noise with specified power */
672  mult1 = sqrt(exp_power[j] / exp_power[last_high_band]);
673  /* XXX: use a table */
674  mult1 = mult1 * pow(10, s->high_band_values[ch][j] * 0.05);
675  mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult);
676  mult1 *= mdct_norm;
677  for(i = 0;i < n; i++) {
678  noise = s->noise_table[s->noise_index];
679  s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
680  *coefs++ = noise *
681  exponents[i<<bsize>>esize] * mult1;
682  }
683  exponents += n<<bsize>>esize;
684  } else {
685  /* coded values + small noise */
686  for(i = 0;i < n; i++) {
687  noise = s->noise_table[s->noise_index];
688  s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
689  *coefs++ = ((*coefs1++) + noise) *
690  exponents[i<<bsize>>esize] * mult;
691  }
692  exponents += n<<bsize>>esize;
693  }
694  }
695 
696  /* very high freqs : noise */
697  n = s->block_len - s->coefs_end[bsize];
698  mult1 = mult * exponents[((-1<<bsize))>>esize];
699  for(i = 0; i < n; i++) {
700  *coefs++ = s->noise_table[s->noise_index] * mult1;
701  s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
702  }
703  } else {
704  /* XXX: optimize more */
705  for(i = 0;i < s->coefs_start; i++)
706  *coefs++ = 0.0;
707  n = nb_coefs[ch];
708  for(i = 0;i < n; i++) {
709  *coefs++ = coefs1[i] * exponents[i<<bsize>>esize] * mult;
710  }
711  n = s->block_len - s->coefs_end[bsize];
712  for(i = 0;i < n; i++)
713  *coefs++ = 0.0;
714  }
715  }
716  }
717 
718 #ifdef TRACE
719  for(ch = 0; ch < s->nb_channels; ch++) {
720  if (s->channel_coded[ch]) {
721  dump_floats(s, "exponents", 3, s->exponents[ch], s->block_len);
722  dump_floats(s, "coefs", 1, s->coefs[ch], s->block_len);
723  }
724  }
725 #endif
726 
727  if (s->ms_stereo && s->channel_coded[1]) {
728  /* nominal case for ms stereo: we do it before mdct */
729  /* no need to optimize this case because it should almost
730  never happen */
731  if (!s->channel_coded[0]) {
732  tprintf(s->avctx, "rare ms-stereo case happened\n");
733  memset(s->coefs[0], 0, sizeof(float) * s->block_len);
734  s->channel_coded[0] = 1;
735  }
736 
737  s->dsp.butterflies_float(s->coefs[0], s->coefs[1], s->block_len);
738  }
739 
740 next:
741  mdct = &s->mdct_ctx[bsize];
742 
743  for(ch = 0; ch < s->nb_channels; ch++) {
744  int n4, index;
745 
746  n4 = s->block_len / 2;
747  if(s->channel_coded[ch]){
748  mdct->imdct_calc(mdct, s->output, s->coefs[ch]);
749  }else if(!(s->ms_stereo && ch==1))
750  memset(s->output, 0, sizeof(s->output));
751 
752  /* multiply by the window and add in the frame */
753  index = (s->frame_len / 2) + s->block_pos - n4;
754  wma_window(s, &s->frame_out[ch][index]);
755  }
756 
757  /* update block number */
758  s->block_num++;
759  s->block_pos += s->block_len;
760  if (s->block_pos >= s->frame_len)
761  return 1;
762  else
763  return 0;
764 }
765 
766 /* decode a frame of frame_len samples */
767 static int wma_decode_frame(WMACodecContext *s, int16_t *samples)
768 {
769  int ret, n, ch, incr;
770  const float *output[MAX_CHANNELS];
771 
772 #ifdef TRACE
773  tprintf(s->avctx, "***decode_frame: %d size=%d\n", s->frame_count++, s->frame_len);
774 #endif
775 
776  /* read each block */
777  s->block_num = 0;
778  s->block_pos = 0;
779  for(;;) {
780  ret = wma_decode_block(s);
781  if (ret < 0)
782  return -1;
783  if (ret)
784  break;
785  }
786 
787  /* convert frame to integer */
788  n = s->frame_len;
789  incr = s->nb_channels;
790  for (ch = 0; ch < MAX_CHANNELS; ch++)
791  output[ch] = s->frame_out[ch];
792  s->fmt_conv.float_to_int16_interleave(samples, output, n, incr);
793  for (ch = 0; ch < incr; ch++) {
794  /* prepare for next block */
795  memmove(&s->frame_out[ch][0], &s->frame_out[ch][n], n * sizeof(float));
796  }
797 
798 #ifdef TRACE
799  dump_shorts(s, "samples", samples, n * s->nb_channels);
800 #endif
801  return 0;
802 }
803 
804 static int wma_decode_superframe(AVCodecContext *avctx, void *data,
805  int *got_frame_ptr, AVPacket *avpkt)
806 {
807  const uint8_t *buf = avpkt->data;
808  int buf_size = avpkt->size;
809  WMACodecContext *s = avctx->priv_data;
810  int nb_frames, bit_offset, i, pos, len, ret;
811  uint8_t *q;
812  int16_t *samples;
813 
814  tprintf(avctx, "***decode_superframe:\n");
815 
816  if(buf_size==0){
817  s->last_superframe_len = 0;
818  return 0;
819  }
820  if (buf_size < s->block_align) {
821  av_log(avctx, AV_LOG_ERROR,
822  "Input packet size too small (%d < %d)\n",
823  buf_size, s->block_align);
824  return AVERROR_INVALIDDATA;
825  }
826  buf_size = s->block_align;
827 
828  init_get_bits(&s->gb, buf, buf_size*8);
829 
830  if (s->use_bit_reservoir) {
831  /* read super frame header */
832  skip_bits(&s->gb, 4); /* super frame index */
833  nb_frames = get_bits(&s->gb, 4) - (s->last_superframe_len <= 0);
834  } else {
835  nb_frames = 1;
836  }
837 
838  /* get output buffer */
839  s->frame.nb_samples = nb_frames * s->frame_len;
840  if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
841  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
842  return ret;
843  }
844  samples = (int16_t *)s->frame.data[0];
845 
846  if (s->use_bit_reservoir) {
847  bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
848  if (bit_offset > get_bits_left(&s->gb)) {
849  av_log(avctx, AV_LOG_ERROR,
850  "Invalid last frame bit offset %d > buf size %d (%d)\n",
851  bit_offset, get_bits_left(&s->gb), buf_size);
852  goto fail;
853  }
854 
855  if (s->last_superframe_len > 0) {
856  // printf("skip=%d\n", s->last_bitoffset);
857  /* add bit_offset bits to last frame */
858  if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
860  goto fail;
862  len = bit_offset;
863  while (len > 7) {
864  *q++ = (get_bits)(&s->gb, 8);
865  len -= 8;
866  }
867  if (len > 0) {
868  *q++ = (get_bits)(&s->gb, len) << (8 - len);
869  }
870  memset(q, 0, FF_INPUT_BUFFER_PADDING_SIZE);
871 
872  /* XXX: bit_offset bits into last frame */
873  init_get_bits(&s->gb, s->last_superframe, s->last_superframe_len * 8 + bit_offset);
874  /* skip unused bits */
875  if (s->last_bitoffset > 0)
876  skip_bits(&s->gb, s->last_bitoffset);
877  /* this frame is stored in the last superframe and in the
878  current one */
879  if (wma_decode_frame(s, samples) < 0)
880  goto fail;
881  samples += s->nb_channels * s->frame_len;
882  nb_frames--;
883  }
884 
885  /* read each frame starting from bit_offset */
886  pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
887  if (pos >= MAX_CODED_SUPERFRAME_SIZE * 8 || pos > buf_size * 8)
888  return AVERROR_INVALIDDATA;
889  init_get_bits(&s->gb, buf + (pos >> 3), (buf_size - (pos >> 3))*8);
890  len = pos & 7;
891  if (len > 0)
892  skip_bits(&s->gb, len);
893 
894  s->reset_block_lengths = 1;
895  for(i=0;i<nb_frames;i++) {
896  if (wma_decode_frame(s, samples) < 0)
897  goto fail;
898  samples += s->nb_channels * s->frame_len;
899  }
900 
901  /* we copy the end of the frame in the last frame buffer */
902  pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
903  s->last_bitoffset = pos & 7;
904  pos >>= 3;
905  len = buf_size - pos;
906  if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
907  av_log(s->avctx, AV_LOG_ERROR, "len %d invalid\n", len);
908  goto fail;
909  }
911  memcpy(s->last_superframe, buf + pos, len);
912  } else {
913  /* single frame decode */
914  if (wma_decode_frame(s, samples) < 0)
915  goto fail;
916  samples += s->nb_channels * s->frame_len;
917  }
918 
919 //av_log(NULL, AV_LOG_ERROR, "%d %d %d %d outbytes:%d eaten:%d\n", s->frame_len_bits, s->block_len_bits, s->frame_len, s->block_len, (int8_t *)samples - (int8_t *)data, s->block_align);
920 
921  *got_frame_ptr = 1;
922  *(AVFrame *)data = s->frame;
923 
924  return s->block_align;
925  fail:
926  /* when error, we reset the bit reservoir */
927  s->last_superframe_len = 0;
928  return -1;
929 }
930 
931 static av_cold void flush(AVCodecContext *avctx)
932 {
933  WMACodecContext *s = avctx->priv_data;
934 
935  s->last_bitoffset=
936  s->last_superframe_len= 0;
937 }
938 
940  .name = "wmav1",
941  .type = AVMEDIA_TYPE_AUDIO,
942  .id = CODEC_ID_WMAV1,
943  .priv_data_size = sizeof(WMACodecContext),
945  .close = ff_wma_end,
947  .flush = flush,
948  .capabilities = CODEC_CAP_DR1,
949  .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"),
950 };
951 
953  .name = "wmav2",
954  .type = AVMEDIA_TYPE_AUDIO,
955  .id = CODEC_ID_WMAV2,
956  .priv_data_size = sizeof(WMACodecContext),
958  .close = ff_wma_end,
960  .flush = flush,
961  .capabilities = CODEC_CAP_DR1,
962  .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"),
963 };