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  if (!avctx->block_align) {
89  av_log(avctx, AV_LOG_ERROR, "block_align is not set\n");
90  return AVERROR(EINVAL);
91  }
92 
93  s->avctx = avctx;
94 
95  /* extract flag infos */
96  flags2 = 0;
97  extradata = avctx->extradata;
98  if (avctx->codec->id == CODEC_ID_WMAV1 && avctx->extradata_size >= 4) {
99  flags2 = AV_RL16(extradata+2);
100  } else if (avctx->codec->id == CODEC_ID_WMAV2 && avctx->extradata_size >= 6) {
101  flags2 = AV_RL16(extradata+4);
102  }
103 // for(i=0; i<avctx->extradata_size; i++)
104 // av_log(NULL, AV_LOG_ERROR, "%02X ", extradata[i]);
105 
106  s->use_exp_vlc = flags2 & 0x0001;
107  s->use_bit_reservoir = flags2 & 0x0002;
108  s->use_variable_block_len = flags2 & 0x0004;
109 
110  if(ff_wma_init(avctx, flags2)<0)
111  return -1;
112 
113  /* init MDCT */
114  for(i = 0; i < s->nb_block_sizes; i++)
115  ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 1, 1.0);
116 
117  if (s->use_noise_coding) {
119  ff_wma_hgain_huffbits, 1, 1,
120  ff_wma_hgain_huffcodes, 2, 2, 0);
121  }
122 
123  if (s->use_exp_vlc) {
124  init_vlc(&s->exp_vlc, EXPVLCBITS, sizeof(ff_aac_scalefactor_bits), //FIXME move out of context
126  ff_aac_scalefactor_code, 4, 4, 0);
127  } else {
129  }
130 
131  avctx->sample_fmt = AV_SAMPLE_FMT_S16;
132 
134  avctx->coded_frame = &s->frame;
135 
136  return 0;
137 }
138 
145 static inline float pow_m1_4(WMACodecContext *s, float x)
146 {
147  union {
148  float f;
149  unsigned int v;
150  } u, t;
151  unsigned int e, m;
152  float a, b;
153 
154  u.f = x;
155  e = u.v >> 23;
156  m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
157  /* build interpolation scale: 1 <= t < 2. */
158  t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
159  a = s->lsp_pow_m_table1[m];
160  b = s->lsp_pow_m_table2[m];
161  return s->lsp_pow_e_table[e] * (a + b * t.f);
162 }
163 
164 static void wma_lsp_to_curve_init(WMACodecContext *s, int frame_len)
165 {
166  float wdel, a, b;
167  int i, e, m;
168 
169  wdel = M_PI / frame_len;
170  for(i=0;i<frame_len;i++)
171  s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
172 
173  /* tables for x^-0.25 computation */
174  for(i=0;i<256;i++) {
175  e = i - 126;
176  s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
177  }
178 
179  /* NOTE: these two tables are needed to avoid two operations in
180  pow_m1_4 */
181  b = 1.0;
182  for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--) {
183  m = (1 << LSP_POW_BITS) + i;
184  a = (float)m * (0.5 / (1 << LSP_POW_BITS));
185  a = pow(a, -0.25);
186  s->lsp_pow_m_table1[i] = 2 * a - b;
187  s->lsp_pow_m_table2[i] = b - a;
188  b = a;
189  }
190 }
191 
197  float *out, float *val_max_ptr,
198  int n, float *lsp)
199 {
200  int i, j;
201  float p, q, w, v, val_max;
202 
203  val_max = 0;
204  for(i=0;i<n;i++) {
205  p = 0.5f;
206  q = 0.5f;
207  w = s->lsp_cos_table[i];
208  for(j=1;j<NB_LSP_COEFS;j+=2){
209  q *= w - lsp[j - 1];
210  p *= w - lsp[j];
211  }
212  p *= p * (2.0f - w);
213  q *= q * (2.0f + w);
214  v = p + q;
215  v = pow_m1_4(s, v);
216  if (v > val_max)
217  val_max = v;
218  out[i] = v;
219  }
220  *val_max_ptr = val_max;
221 }
222 
226 static void decode_exp_lsp(WMACodecContext *s, int ch)
227 {
228  float lsp_coefs[NB_LSP_COEFS];
229  int val, i;
230 
231  for(i = 0; i < NB_LSP_COEFS; i++) {
232  if (i == 0 || i >= 8)
233  val = get_bits(&s->gb, 3);
234  else
235  val = get_bits(&s->gb, 4);
236  lsp_coefs[i] = ff_wma_lsp_codebook[i][val];
237  }
238 
239  wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
240  s->block_len, lsp_coefs);
241 }
242 
244 static const float pow_tab[] = {
245  1.7782794100389e-04, 2.0535250264571e-04,
246  2.3713737056617e-04, 2.7384196342644e-04,
247  3.1622776601684e-04, 3.6517412725484e-04,
248  4.2169650342858e-04, 4.8696752516586e-04,
249  5.6234132519035e-04, 6.4938163157621e-04,
250  7.4989420933246e-04, 8.6596432336006e-04,
251  1.0000000000000e-03, 1.1547819846895e-03,
252  1.3335214321633e-03, 1.5399265260595e-03,
253  1.7782794100389e-03, 2.0535250264571e-03,
254  2.3713737056617e-03, 2.7384196342644e-03,
255  3.1622776601684e-03, 3.6517412725484e-03,
256  4.2169650342858e-03, 4.8696752516586e-03,
257  5.6234132519035e-03, 6.4938163157621e-03,
258  7.4989420933246e-03, 8.6596432336006e-03,
259  1.0000000000000e-02, 1.1547819846895e-02,
260  1.3335214321633e-02, 1.5399265260595e-02,
261  1.7782794100389e-02, 2.0535250264571e-02,
262  2.3713737056617e-02, 2.7384196342644e-02,
263  3.1622776601684e-02, 3.6517412725484e-02,
264  4.2169650342858e-02, 4.8696752516586e-02,
265  5.6234132519035e-02, 6.4938163157621e-02,
266  7.4989420933246e-02, 8.6596432336007e-02,
267  1.0000000000000e-01, 1.1547819846895e-01,
268  1.3335214321633e-01, 1.5399265260595e-01,
269  1.7782794100389e-01, 2.0535250264571e-01,
270  2.3713737056617e-01, 2.7384196342644e-01,
271  3.1622776601684e-01, 3.6517412725484e-01,
272  4.2169650342858e-01, 4.8696752516586e-01,
273  5.6234132519035e-01, 6.4938163157621e-01,
274  7.4989420933246e-01, 8.6596432336007e-01,
275  1.0000000000000e+00, 1.1547819846895e+00,
276  1.3335214321633e+00, 1.5399265260595e+00,
277  1.7782794100389e+00, 2.0535250264571e+00,
278  2.3713737056617e+00, 2.7384196342644e+00,
279  3.1622776601684e+00, 3.6517412725484e+00,
280  4.2169650342858e+00, 4.8696752516586e+00,
281  5.6234132519035e+00, 6.4938163157621e+00,
282  7.4989420933246e+00, 8.6596432336007e+00,
283  1.0000000000000e+01, 1.1547819846895e+01,
284  1.3335214321633e+01, 1.5399265260595e+01,
285  1.7782794100389e+01, 2.0535250264571e+01,
286  2.3713737056617e+01, 2.7384196342644e+01,
287  3.1622776601684e+01, 3.6517412725484e+01,
288  4.2169650342858e+01, 4.8696752516586e+01,
289  5.6234132519035e+01, 6.4938163157621e+01,
290  7.4989420933246e+01, 8.6596432336007e+01,
291  1.0000000000000e+02, 1.1547819846895e+02,
292  1.3335214321633e+02, 1.5399265260595e+02,
293  1.7782794100389e+02, 2.0535250264571e+02,
294  2.3713737056617e+02, 2.7384196342644e+02,
295  3.1622776601684e+02, 3.6517412725484e+02,
296  4.2169650342858e+02, 4.8696752516586e+02,
297  5.6234132519035e+02, 6.4938163157621e+02,
298  7.4989420933246e+02, 8.6596432336007e+02,
299  1.0000000000000e+03, 1.1547819846895e+03,
300  1.3335214321633e+03, 1.5399265260595e+03,
301  1.7782794100389e+03, 2.0535250264571e+03,
302  2.3713737056617e+03, 2.7384196342644e+03,
303  3.1622776601684e+03, 3.6517412725484e+03,
304  4.2169650342858e+03, 4.8696752516586e+03,
305  5.6234132519035e+03, 6.4938163157621e+03,
306  7.4989420933246e+03, 8.6596432336007e+03,
307  1.0000000000000e+04, 1.1547819846895e+04,
308  1.3335214321633e+04, 1.5399265260595e+04,
309  1.7782794100389e+04, 2.0535250264571e+04,
310  2.3713737056617e+04, 2.7384196342644e+04,
311  3.1622776601684e+04, 3.6517412725484e+04,
312  4.2169650342858e+04, 4.8696752516586e+04,
313  5.6234132519035e+04, 6.4938163157621e+04,
314  7.4989420933246e+04, 8.6596432336007e+04,
315  1.0000000000000e+05, 1.1547819846895e+05,
316  1.3335214321633e+05, 1.5399265260595e+05,
317  1.7782794100389e+05, 2.0535250264571e+05,
318  2.3713737056617e+05, 2.7384196342644e+05,
319  3.1622776601684e+05, 3.6517412725484e+05,
320  4.2169650342858e+05, 4.8696752516586e+05,
321  5.6234132519035e+05, 6.4938163157621e+05,
322  7.4989420933246e+05, 8.6596432336007e+05,
323 };
324 
328 static int decode_exp_vlc(WMACodecContext *s, int ch)
329 {
330  int last_exp, n, code;
331  const uint16_t *ptr;
332  float v, max_scale;
333  uint32_t *q, *q_end, iv;
334  const float *ptab = pow_tab + 60;
335  const uint32_t *iptab = (const uint32_t*)ptab;
336 
337  ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
338  q = (uint32_t *)s->exponents[ch];
339  q_end = q + s->block_len;
340  max_scale = 0;
341  if (s->version == 1) {
342  last_exp = get_bits(&s->gb, 5) + 10;
343  v = ptab[last_exp];
344  iv = iptab[last_exp];
345  max_scale = v;
346  n = *ptr++;
347  switch (n & 3) do {
348  case 0: *q++ = iv;
349  case 3: *q++ = iv;
350  case 2: *q++ = iv;
351  case 1: *q++ = iv;
352  } while ((n -= 4) > 0);
353  }else
354  last_exp = 36;
355 
356  while (q < q_end) {
357  code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX);
358  if (code < 0){
359  av_log(s->avctx, AV_LOG_ERROR, "Exponent vlc invalid\n");
360  return -1;
361  }
362  /* NOTE: this offset is the same as MPEG4 AAC ! */
363  last_exp += code - 60;
364  if ((unsigned)last_exp + 60 >= FF_ARRAY_ELEMS(pow_tab)) {
365  av_log(s->avctx, AV_LOG_ERROR, "Exponent out of range: %d\n",
366  last_exp);
367  return -1;
368  }
369  v = ptab[last_exp];
370  iv = iptab[last_exp];
371  if (v > max_scale)
372  max_scale = v;
373  n = *ptr++;
374  switch (n & 3) do {
375  case 0: *q++ = iv;
376  case 3: *q++ = iv;
377  case 2: *q++ = iv;
378  case 1: *q++ = iv;
379  } while ((n -= 4) > 0);
380  }
381  s->max_exponent[ch] = max_scale;
382  return 0;
383 }
384 
385 
392 static void wma_window(WMACodecContext *s, float *out)
393 {
394  float *in = s->output;
395  int block_len, bsize, n;
396 
397  /* left part */
398  if (s->block_len_bits <= s->prev_block_len_bits) {
399  block_len = s->block_len;
400  bsize = s->frame_len_bits - s->block_len_bits;
401 
402  s->dsp.vector_fmul_add(out, in, s->windows[bsize],
403  out, block_len);
404 
405  } else {
406  block_len = 1 << s->prev_block_len_bits;
407  n = (s->block_len - block_len) / 2;
408  bsize = s->frame_len_bits - s->prev_block_len_bits;
409 
410  s->dsp.vector_fmul_add(out+n, in+n, s->windows[bsize],
411  out+n, block_len);
412 
413  memcpy(out+n+block_len, in+n+block_len, n*sizeof(float));
414  }
415 
416  out += s->block_len;
417  in += s->block_len;
418 
419  /* right part */
420  if (s->block_len_bits <= s->next_block_len_bits) {
421  block_len = s->block_len;
422  bsize = s->frame_len_bits - s->block_len_bits;
423 
424  s->dsp.vector_fmul_reverse(out, in, s->windows[bsize], block_len);
425 
426  } else {
427  block_len = 1 << s->next_block_len_bits;
428  n = (s->block_len - block_len) / 2;
429  bsize = s->frame_len_bits - s->next_block_len_bits;
430 
431  memcpy(out, in, n*sizeof(float));
432 
433  s->dsp.vector_fmul_reverse(out+n, in+n, s->windows[bsize], block_len);
434 
435  memset(out+n+block_len, 0, n*sizeof(float));
436  }
437 }
438 
439 
445 {
446  int n, v, a, ch, bsize;
447  int coef_nb_bits, total_gain;
448  int nb_coefs[MAX_CHANNELS];
449  float mdct_norm;
450  FFTContext *mdct;
451 
452 #ifdef TRACE
453  tprintf(s->avctx, "***decode_block: %d:%d\n", s->frame_count - 1, s->block_num);
454 #endif
455 
456  /* compute current block length */
457  if (s->use_variable_block_len) {
458  n = av_log2(s->nb_block_sizes - 1) + 1;
459 
460  if (s->reset_block_lengths) {
461  s->reset_block_lengths = 0;
462  v = get_bits(&s->gb, n);
463  if (v >= s->nb_block_sizes){
464  av_log(s->avctx, AV_LOG_ERROR, "prev_block_len_bits %d out of range\n", s->frame_len_bits - v);
465  return -1;
466  }
468  v = get_bits(&s->gb, n);
469  if (v >= s->nb_block_sizes){
470  av_log(s->avctx, AV_LOG_ERROR, "block_len_bits %d out of range\n", s->frame_len_bits - v);
471  return -1;
472  }
473  s->block_len_bits = s->frame_len_bits - v;
474  } else {
475  /* update block lengths */
478  }
479  v = get_bits(&s->gb, n);
480  if (v >= s->nb_block_sizes){
481  av_log(s->avctx, AV_LOG_ERROR, "next_block_len_bits %d out of range\n", s->frame_len_bits - v);
482  return -1;
483  }
485  } else {
486  /* fixed block len */
490  }
491 
492  /* now check if the block length is coherent with the frame length */
493  s->block_len = 1 << s->block_len_bits;
494  if ((s->block_pos + s->block_len) > s->frame_len){
495  av_log(s->avctx, AV_LOG_ERROR, "frame_len overflow\n");
496  return -1;
497  }
498 
499  if (s->nb_channels == 2) {
500  s->ms_stereo = get_bits1(&s->gb);
501  }
502  v = 0;
503  for(ch = 0; ch < s->nb_channels; ch++) {
504  a = get_bits1(&s->gb);
505  s->channel_coded[ch] = a;
506  v |= a;
507  }
508 
509  bsize = s->frame_len_bits - s->block_len_bits;
510 
511  /* if no channel coded, no need to go further */
512  /* XXX: fix potential framing problems */
513  if (!v)
514  goto next;
515 
516  /* read total gain and extract corresponding number of bits for
517  coef escape coding */
518  total_gain = 1;
519  for(;;) {
520  a = get_bits(&s->gb, 7);
521  total_gain += a;
522  if (a != 127)
523  break;
524  }
525 
526  coef_nb_bits= ff_wma_total_gain_to_bits(total_gain);
527 
528  /* compute number of coefficients */
529  n = s->coefs_end[bsize] - s->coefs_start;
530  for(ch = 0; ch < s->nb_channels; ch++)
531  nb_coefs[ch] = n;
532 
533  /* complex coding */
534  if (s->use_noise_coding) {
535 
536  for(ch = 0; ch < s->nb_channels; ch++) {
537  if (s->channel_coded[ch]) {
538  int i, n, a;
539  n = s->exponent_high_sizes[bsize];
540  for(i=0;i<n;i++) {
541  a = get_bits1(&s->gb);
542  s->high_band_coded[ch][i] = a;
543  /* if noise coding, the coefficients are not transmitted */
544  if (a)
545  nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
546  }
547  }
548  }
549  for(ch = 0; ch < s->nb_channels; ch++) {
550  if (s->channel_coded[ch]) {
551  int i, n, val, code;
552 
553  n = s->exponent_high_sizes[bsize];
554  val = (int)0x80000000;
555  for(i=0;i<n;i++) {
556  if (s->high_band_coded[ch][i]) {
557  if (val == (int)0x80000000) {
558  val = get_bits(&s->gb, 7) - 19;
559  } else {
560  code = get_vlc2(&s->gb, s->hgain_vlc.table, HGAINVLCBITS, HGAINMAX);
561  if (code < 0){
562  av_log(s->avctx, AV_LOG_ERROR, "hgain vlc invalid\n");
563  return -1;
564  }
565  val += code - 18;
566  }
567  s->high_band_values[ch][i] = val;
568  }
569  }
570  }
571  }
572  }
573 
574  /* exponents can be reused in short blocks. */
575  if ((s->block_len_bits == s->frame_len_bits) ||
576  get_bits1(&s->gb)) {
577  for(ch = 0; ch < s->nb_channels; ch++) {
578  if (s->channel_coded[ch]) {
579  if (s->use_exp_vlc) {
580  if (decode_exp_vlc(s, ch) < 0)
581  return -1;
582  } else {
583  decode_exp_lsp(s, ch);
584  }
585  s->exponents_bsize[ch] = bsize;
586  }
587  }
588  }
589 
590  /* parse spectral coefficients : just RLE encoding */
591  for(ch = 0; ch < s->nb_channels; ch++) {
592  if (s->channel_coded[ch]) {
593  int tindex;
594  WMACoef* ptr = &s->coefs1[ch][0];
595 
596  /* special VLC tables are used for ms stereo because
597  there is potentially less energy there */
598  tindex = (ch == 1 && s->ms_stereo);
599  memset(ptr, 0, s->block_len * sizeof(WMACoef));
600  ff_wma_run_level_decode(s->avctx, &s->gb, &s->coef_vlc[tindex],
601  s->level_table[tindex], s->run_table[tindex],
602  0, ptr, 0, nb_coefs[ch],
603  s->block_len, s->frame_len_bits, coef_nb_bits);
604  }
605  if (s->version == 1 && s->nb_channels >= 2) {
606  align_get_bits(&s->gb);
607  }
608  }
609 
610  /* normalize */
611  {
612  int n4 = s->block_len / 2;
613  mdct_norm = 1.0 / (float)n4;
614  if (s->version == 1) {
615  mdct_norm *= sqrt(n4);
616  }
617  }
618 
619  /* finally compute the MDCT coefficients */
620  for(ch = 0; ch < s->nb_channels; ch++) {
621  if (s->channel_coded[ch]) {
622  WMACoef *coefs1;
623  float *coefs, *exponents, mult, mult1, noise;
624  int i, j, n, n1, last_high_band, esize;
625  float exp_power[HIGH_BAND_MAX_SIZE];
626 
627  coefs1 = s->coefs1[ch];
628  exponents = s->exponents[ch];
629  esize = s->exponents_bsize[ch];
630  mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
631  mult *= mdct_norm;
632  coefs = s->coefs[ch];
633  if (s->use_noise_coding) {
634  mult1 = mult;
635  /* very low freqs : noise */
636  for(i = 0;i < s->coefs_start; i++) {
637  *coefs++ = s->noise_table[s->noise_index] *
638  exponents[i<<bsize>>esize] * mult1;
639  s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
640  }
641 
642  n1 = s->exponent_high_sizes[bsize];
643 
644  /* compute power of high bands */
645  exponents = s->exponents[ch] +
646  (s->high_band_start[bsize]<<bsize>>esize);
647  last_high_band = 0; /* avoid warning */
648  for(j=0;j<n1;j++) {
650  s->block_len_bits][j];
651  if (s->high_band_coded[ch][j]) {
652  float e2, v;
653  e2 = 0;
654  for(i = 0;i < n; i++) {
655  v = exponents[i<<bsize>>esize];
656  e2 += v * v;
657  }
658  exp_power[j] = e2 / n;
659  last_high_band = j;
660  tprintf(s->avctx, "%d: power=%f (%d)\n", j, exp_power[j], n);
661  }
662  exponents += n<<bsize>>esize;
663  }
664 
665  /* main freqs and high freqs */
666  exponents = s->exponents[ch] + (s->coefs_start<<bsize>>esize);
667  for(j=-1;j<n1;j++) {
668  if (j < 0) {
669  n = s->high_band_start[bsize] -
670  s->coefs_start;
671  } else {
673  s->block_len_bits][j];
674  }
675  if (j >= 0 && s->high_band_coded[ch][j]) {
676  /* use noise with specified power */
677  mult1 = sqrt(exp_power[j] / exp_power[last_high_band]);
678  /* XXX: use a table */
679  mult1 = mult1 * pow(10, s->high_band_values[ch][j] * 0.05);
680  mult1 = mult1 / (s->max_exponent[ch] * s->noise_mult);
681  mult1 *= mdct_norm;
682  for(i = 0;i < n; i++) {
683  noise = s->noise_table[s->noise_index];
684  s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
685  *coefs++ = noise *
686  exponents[i<<bsize>>esize] * mult1;
687  }
688  exponents += n<<bsize>>esize;
689  } else {
690  /* coded values + small noise */
691  for(i = 0;i < n; i++) {
692  noise = s->noise_table[s->noise_index];
693  s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
694  *coefs++ = ((*coefs1++) + noise) *
695  exponents[i<<bsize>>esize] * mult;
696  }
697  exponents += n<<bsize>>esize;
698  }
699  }
700 
701  /* very high freqs : noise */
702  n = s->block_len - s->coefs_end[bsize];
703  mult1 = mult * exponents[((-1<<bsize))>>esize];
704  for(i = 0; i < n; i++) {
705  *coefs++ = s->noise_table[s->noise_index] * mult1;
706  s->noise_index = (s->noise_index + 1) & (NOISE_TAB_SIZE - 1);
707  }
708  } else {
709  /* XXX: optimize more */
710  for(i = 0;i < s->coefs_start; i++)
711  *coefs++ = 0.0;
712  n = nb_coefs[ch];
713  for(i = 0;i < n; i++) {
714  *coefs++ = coefs1[i] * exponents[i<<bsize>>esize] * mult;
715  }
716  n = s->block_len - s->coefs_end[bsize];
717  for(i = 0;i < n; i++)
718  *coefs++ = 0.0;
719  }
720  }
721  }
722 
723 #ifdef TRACE
724  for(ch = 0; ch < s->nb_channels; ch++) {
725  if (s->channel_coded[ch]) {
726  dump_floats(s, "exponents", 3, s->exponents[ch], s->block_len);
727  dump_floats(s, "coefs", 1, s->coefs[ch], s->block_len);
728  }
729  }
730 #endif
731 
732  if (s->ms_stereo && s->channel_coded[1]) {
733  /* nominal case for ms stereo: we do it before mdct */
734  /* no need to optimize this case because it should almost
735  never happen */
736  if (!s->channel_coded[0]) {
737  tprintf(s->avctx, "rare ms-stereo case happened\n");
738  memset(s->coefs[0], 0, sizeof(float) * s->block_len);
739  s->channel_coded[0] = 1;
740  }
741 
742  s->dsp.butterflies_float(s->coefs[0], s->coefs[1], s->block_len);
743  }
744 
745 next:
746  mdct = &s->mdct_ctx[bsize];
747 
748  for(ch = 0; ch < s->nb_channels; ch++) {
749  int n4, index;
750 
751  n4 = s->block_len / 2;
752  if(s->channel_coded[ch]){
753  mdct->imdct_calc(mdct, s->output, s->coefs[ch]);
754  }else if(!(s->ms_stereo && ch==1))
755  memset(s->output, 0, sizeof(s->output));
756 
757  /* multiply by the window and add in the frame */
758  index = (s->frame_len / 2) + s->block_pos - n4;
759  wma_window(s, &s->frame_out[ch][index]);
760  }
761 
762  /* update block number */
763  s->block_num++;
764  s->block_pos += s->block_len;
765  if (s->block_pos >= s->frame_len)
766  return 1;
767  else
768  return 0;
769 }
770 
771 /* decode a frame of frame_len samples */
772 static int wma_decode_frame(WMACodecContext *s, int16_t *samples)
773 {
774  int ret, n, ch, incr;
775  const float *output[MAX_CHANNELS];
776 
777 #ifdef TRACE
778  tprintf(s->avctx, "***decode_frame: %d size=%d\n", s->frame_count++, s->frame_len);
779 #endif
780 
781  /* read each block */
782  s->block_num = 0;
783  s->block_pos = 0;
784  for(;;) {
785  ret = wma_decode_block(s);
786  if (ret < 0)
787  return -1;
788  if (ret)
789  break;
790  }
791 
792  /* convert frame to integer */
793  n = s->frame_len;
794  incr = s->nb_channels;
795  for (ch = 0; ch < MAX_CHANNELS; ch++)
796  output[ch] = s->frame_out[ch];
797  s->fmt_conv.float_to_int16_interleave(samples, output, n, incr);
798  for (ch = 0; ch < incr; ch++) {
799  /* prepare for next block */
800  memmove(&s->frame_out[ch][0], &s->frame_out[ch][n], n * sizeof(float));
801  }
802 
803 #ifdef TRACE
804  dump_shorts(s, "samples", samples, n * s->nb_channels);
805 #endif
806  return 0;
807 }
808 
809 static int wma_decode_superframe(AVCodecContext *avctx, void *data,
810  int *got_frame_ptr, AVPacket *avpkt)
811 {
812  const uint8_t *buf = avpkt->data;
813  int buf_size = avpkt->size;
814  WMACodecContext *s = avctx->priv_data;
815  int nb_frames, bit_offset, i, pos, len, ret;
816  uint8_t *q;
817  int16_t *samples;
818 
819  tprintf(avctx, "***decode_superframe:\n");
820 
821  if(buf_size==0){
822  s->last_superframe_len = 0;
823  return 0;
824  }
825  if (buf_size < s->block_align) {
826  av_log(avctx, AV_LOG_ERROR,
827  "Input packet size too small (%d < %d)\n",
828  buf_size, s->block_align);
829  return AVERROR_INVALIDDATA;
830  }
831  buf_size = s->block_align;
832 
833  init_get_bits(&s->gb, buf, buf_size*8);
834 
835  if (s->use_bit_reservoir) {
836  /* read super frame header */
837  skip_bits(&s->gb, 4); /* super frame index */
838  nb_frames = get_bits(&s->gb, 4) - (s->last_superframe_len <= 0);
839  } else {
840  nb_frames = 1;
841  }
842 
843  /* get output buffer */
844  s->frame.nb_samples = nb_frames * s->frame_len;
845  if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
846  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
847  return ret;
848  }
849  samples = (int16_t *)s->frame.data[0];
850 
851  if (s->use_bit_reservoir) {
852  bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
853  if (bit_offset > get_bits_left(&s->gb)) {
854  av_log(avctx, AV_LOG_ERROR,
855  "Invalid last frame bit offset %d > buf size %d (%d)\n",
856  bit_offset, get_bits_left(&s->gb), buf_size);
857  goto fail;
858  }
859 
860  if (s->last_superframe_len > 0) {
861  // printf("skip=%d\n", s->last_bitoffset);
862  /* add bit_offset bits to last frame */
863  if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
865  goto fail;
867  len = bit_offset;
868  while (len > 7) {
869  *q++ = (get_bits)(&s->gb, 8);
870  len -= 8;
871  }
872  if (len > 0) {
873  *q++ = (get_bits)(&s->gb, len) << (8 - len);
874  }
875  memset(q, 0, FF_INPUT_BUFFER_PADDING_SIZE);
876 
877  /* XXX: bit_offset bits into last frame */
878  init_get_bits(&s->gb, s->last_superframe, s->last_superframe_len * 8 + bit_offset);
879  /* skip unused bits */
880  if (s->last_bitoffset > 0)
881  skip_bits(&s->gb, s->last_bitoffset);
882  /* this frame is stored in the last superframe and in the
883  current one */
884  if (wma_decode_frame(s, samples) < 0)
885  goto fail;
886  samples += s->nb_channels * s->frame_len;
887  nb_frames--;
888  }
889 
890  /* read each frame starting from bit_offset */
891  pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
892  if (pos >= MAX_CODED_SUPERFRAME_SIZE * 8 || pos > buf_size * 8)
893  return AVERROR_INVALIDDATA;
894  init_get_bits(&s->gb, buf + (pos >> 3), (buf_size - (pos >> 3))*8);
895  len = pos & 7;
896  if (len > 0)
897  skip_bits(&s->gb, len);
898 
899  s->reset_block_lengths = 1;
900  for(i=0;i<nb_frames;i++) {
901  if (wma_decode_frame(s, samples) < 0)
902  goto fail;
903  samples += s->nb_channels * s->frame_len;
904  }
905 
906  /* we copy the end of the frame in the last frame buffer */
907  pos = get_bits_count(&s->gb) + ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
908  s->last_bitoffset = pos & 7;
909  pos >>= 3;
910  len = buf_size - pos;
911  if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
912  av_log(s->avctx, AV_LOG_ERROR, "len %d invalid\n", len);
913  goto fail;
914  }
916  memcpy(s->last_superframe, buf + pos, len);
917  } else {
918  /* single frame decode */
919  if (wma_decode_frame(s, samples) < 0)
920  goto fail;
921  samples += s->nb_channels * s->frame_len;
922  }
923 
924 //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);
925 
926  *got_frame_ptr = 1;
927  *(AVFrame *)data = s->frame;
928 
929  return s->block_align;
930  fail:
931  /* when error, we reset the bit reservoir */
932  s->last_superframe_len = 0;
933  return -1;
934 }
935 
936 static av_cold void flush(AVCodecContext *avctx)
937 {
938  WMACodecContext *s = avctx->priv_data;
939 
940  s->last_bitoffset=
941  s->last_superframe_len= 0;
942 }
943 
945  .name = "wmav1",
946  .type = AVMEDIA_TYPE_AUDIO,
947  .id = CODEC_ID_WMAV1,
948  .priv_data_size = sizeof(WMACodecContext),
950  .close = ff_wma_end,
952  .flush = flush,
953  .capabilities = CODEC_CAP_DR1,
954  .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"),
955 };
956 
958  .name = "wmav2",
959  .type = AVMEDIA_TYPE_AUDIO,
960  .id = CODEC_ID_WMAV2,
961  .priv_data_size = sizeof(WMACodecContext),
963  .close = ff_wma_end,
965  .flush = flush,
966  .capabilities = CODEC_CAP_DR1,
967  .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"),
968 };