alsdec.c
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1 /*
2  * MPEG-4 ALS decoder
3  * Copyright (c) 2009 Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
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 
29 //#define DEBUG
30 
31 
32 #include "avcodec.h"
33 #include "get_bits.h"
34 #include "unary.h"
35 #include "mpeg4audio.h"
36 #include "bytestream.h"
37 #include "bgmc.h"
38 #include "dsputil.h"
39 #include "libavutil/samplefmt.h"
40 #include "libavutil/crc.h"
41 
42 #include <stdint.h>
43 
48 static const int8_t parcor_rice_table[3][20][2] = {
49  { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
50  { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
51  { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
52  { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
53  { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
54  { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
55  {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
56  { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
57  { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
58  { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
59  {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
60  { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
61 };
62 
63 
69 static const int16_t parcor_scaled_values[] = {
70  -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
71  -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
72  -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
73  -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
74  -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
75  -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
76  -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
77  -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
78  -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
79  -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
80  -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
81  -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
82  -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
83  -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
84  -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
85  -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
86  -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
87  -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
88  -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
89  -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
90  -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
91  -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
92  -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
93  46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
94  143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
95  244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
96  349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
97  458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
98  571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
99  688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
100  810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
101  935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
102 };
103 
104 
108 static const uint8_t ltp_gain_values [4][4] = {
109  { 0, 8, 16, 24},
110  {32, 40, 48, 56},
111  {64, 70, 76, 82},
112  {88, 92, 96, 100}
113 };
114 
115 
119 static const int16_t mcc_weightings[] = {
120  204, 192, 179, 166, 153, 140, 128, 115,
121  102, 89, 76, 64, 51, 38, 25, 12,
122  0, -12, -25, -38, -51, -64, -76, -89,
123  -102, -115, -128, -140, -153, -166, -179, -192
124 };
125 
126 
129 static const uint8_t tail_code[16][6] = {
130  { 74, 44, 25, 13, 7, 3},
131  { 68, 42, 24, 13, 7, 3},
132  { 58, 39, 23, 13, 7, 3},
133  {126, 70, 37, 19, 10, 5},
134  {132, 70, 37, 20, 10, 5},
135  {124, 70, 38, 20, 10, 5},
136  {120, 69, 37, 20, 11, 5},
137  {116, 67, 37, 20, 11, 5},
138  {108, 66, 36, 20, 10, 5},
139  {102, 62, 36, 20, 10, 5},
140  { 88, 58, 34, 19, 10, 5},
141  {162, 89, 49, 25, 13, 7},
142  {156, 87, 49, 26, 14, 7},
143  {150, 86, 47, 26, 14, 7},
144  {142, 84, 47, 26, 14, 7},
145  {131, 79, 46, 26, 14, 7}
146 };
147 
148 
149 enum RA_Flag {
153 };
154 
155 
156 typedef struct {
157  uint32_t samples;
159  int floating;
160  int msb_first;
167  int max_order;
169  int bgmc;
170  int sb_part;
172  int mc_coding;
174  int chan_sort;
175  int rlslms;
177  int *chan_pos;
180 
181 
182 typedef struct {
188  int weighting[6];
190 
191 
192 typedef struct {
198  const AVCRC *crc_table;
199  uint32_t crc_org;
200  uint32_t crc;
201  unsigned int cur_frame_length;
202  unsigned int frame_id;
203  unsigned int js_switch;
204  unsigned int num_blocks;
205  unsigned int s_max;
206  uint8_t *bgmc_lut;
209  int *const_block;
210  unsigned int *shift_lsbs;
211  unsigned int *opt_order;
213  int *use_ltp;
214  int *ltp_lag;
215  int **ltp_gain;
217  int32_t **quant_cof;
218  int32_t *quant_cof_buffer;
219  int32_t **lpc_cof;
220  int32_t *lpc_cof_buffer;
225  int32_t *prev_raw_samples;
226  int32_t **raw_samples;
227  int32_t *raw_buffer;
228  uint8_t *crc_buffer;
229 } ALSDecContext;
230 
231 
232 typedef struct {
233  unsigned int block_length;
234  unsigned int ra_block;
235  int *const_block;
236  int js_blocks;
237  unsigned int *shift_lsbs;
238  unsigned int *opt_order;
240  int *use_ltp;
241  int *ltp_lag;
242  int *ltp_gain;
243  int32_t *quant_cof;
244  int32_t *lpc_cof;
245  int32_t *raw_samples;
246  int32_t *prev_raw_samples;
247  int32_t *raw_other;
248 } ALSBlockData;
249 
250 
252 {
253 #ifdef DEBUG
254  AVCodecContext *avctx = ctx->avctx;
255  ALSSpecificConfig *sconf = &ctx->sconf;
256 
257  av_dlog(avctx, "resolution = %i\n", sconf->resolution);
258  av_dlog(avctx, "floating = %i\n", sconf->floating);
259  av_dlog(avctx, "frame_length = %i\n", sconf->frame_length);
260  av_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance);
261  av_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag);
262  av_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order);
263  av_dlog(avctx, "coef_table = %i\n", sconf->coef_table);
264  av_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
265  av_dlog(avctx, "max_order = %i\n", sconf->max_order);
266  av_dlog(avctx, "block_switching = %i\n", sconf->block_switching);
267  av_dlog(avctx, "bgmc = %i\n", sconf->bgmc);
268  av_dlog(avctx, "sb_part = %i\n", sconf->sb_part);
269  av_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
270  av_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding);
271  av_dlog(avctx, "chan_config = %i\n", sconf->chan_config);
272  av_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort);
273  av_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms);
274  av_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
275 #endif
276 }
277 
278 
282 {
283  GetBitContext gb;
284  uint64_t ht_size;
285  int i, config_offset;
286  MPEG4AudioConfig m4ac;
287  ALSSpecificConfig *sconf = &ctx->sconf;
288  AVCodecContext *avctx = ctx->avctx;
289  uint32_t als_id, header_size, trailer_size;
290 
291  init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
292 
293  config_offset = avpriv_mpeg4audio_get_config(&m4ac, avctx->extradata,
294  avctx->extradata_size * 8, 1);
295 
296  if (config_offset < 0)
297  return -1;
298 
299  skip_bits_long(&gb, config_offset);
300 
301  if (get_bits_left(&gb) < (30 << 3))
302  return -1;
303 
304  // read the fixed items
305  als_id = get_bits_long(&gb, 32);
306  avctx->sample_rate = m4ac.sample_rate;
307  skip_bits_long(&gb, 32); // sample rate already known
308  sconf->samples = get_bits_long(&gb, 32);
309  avctx->channels = m4ac.channels;
310  skip_bits(&gb, 16); // number of channels already knwon
311  skip_bits(&gb, 3); // skip file_type
312  sconf->resolution = get_bits(&gb, 3);
313  sconf->floating = get_bits1(&gb);
314  sconf->msb_first = get_bits1(&gb);
315  sconf->frame_length = get_bits(&gb, 16) + 1;
316  sconf->ra_distance = get_bits(&gb, 8);
317  sconf->ra_flag = get_bits(&gb, 2);
318  sconf->adapt_order = get_bits1(&gb);
319  sconf->coef_table = get_bits(&gb, 2);
320  sconf->long_term_prediction = get_bits1(&gb);
321  sconf->max_order = get_bits(&gb, 10);
322  sconf->block_switching = get_bits(&gb, 2);
323  sconf->bgmc = get_bits1(&gb);
324  sconf->sb_part = get_bits1(&gb);
325  sconf->joint_stereo = get_bits1(&gb);
326  sconf->mc_coding = get_bits1(&gb);
327  sconf->chan_config = get_bits1(&gb);
328  sconf->chan_sort = get_bits1(&gb);
329  sconf->crc_enabled = get_bits1(&gb);
330  sconf->rlslms = get_bits1(&gb);
331  skip_bits(&gb, 5); // skip 5 reserved bits
332  skip_bits1(&gb); // skip aux_data_enabled
333 
334 
335  // check for ALSSpecificConfig struct
336  if (als_id != MKBETAG('A','L','S','\0'))
337  return -1;
338 
339  ctx->cur_frame_length = sconf->frame_length;
340 
341  // read channel config
342  if (sconf->chan_config)
343  sconf->chan_config_info = get_bits(&gb, 16);
344  // TODO: use this to set avctx->channel_layout
345 
346 
347  // read channel sorting
348  if (sconf->chan_sort && avctx->channels > 1) {
349  int chan_pos_bits = av_ceil_log2(avctx->channels);
350  int bits_needed = avctx->channels * chan_pos_bits + 7;
351  if (get_bits_left(&gb) < bits_needed)
352  return -1;
353 
354  if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
355  return AVERROR(ENOMEM);
356 
357  for (i = 0; i < avctx->channels; i++)
358  sconf->chan_pos[i] = get_bits(&gb, chan_pos_bits);
359 
360  align_get_bits(&gb);
361  // TODO: use this to actually do channel sorting
362  } else {
363  sconf->chan_sort = 0;
364  }
365 
366 
367  // read fixed header and trailer sizes,
368  // if size = 0xFFFFFFFF then there is no data field!
369  if (get_bits_left(&gb) < 64)
370  return -1;
371 
372  header_size = get_bits_long(&gb, 32);
373  trailer_size = get_bits_long(&gb, 32);
374  if (header_size == 0xFFFFFFFF)
375  header_size = 0;
376  if (trailer_size == 0xFFFFFFFF)
377  trailer_size = 0;
378 
379  ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
380 
381 
382  // skip the header and trailer data
383  if (get_bits_left(&gb) < ht_size)
384  return -1;
385 
386  if (ht_size > INT32_MAX)
387  return -1;
388 
389  skip_bits_long(&gb, ht_size);
390 
391 
392  // initialize CRC calculation
393  if (sconf->crc_enabled) {
394  if (get_bits_left(&gb) < 32)
395  return -1;
396 
397  if (avctx->err_recognition & AV_EF_CRCCHECK) {
399  ctx->crc = 0xFFFFFFFF;
400  ctx->crc_org = ~get_bits_long(&gb, 32);
401  } else
402  skip_bits_long(&gb, 32);
403  }
404 
405 
406  // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
407 
409 
410  return 0;
411 }
412 
413 
417 {
418  ALSSpecificConfig *sconf = &ctx->sconf;
419  int error = 0;
420 
421  // report unsupported feature and set error value
422  #define MISSING_ERR(cond, str, errval) \
423  { \
424  if (cond) { \
425  av_log_missing_feature(ctx->avctx, str, 0); \
426  error = errval; \
427  } \
428  }
429 
430  MISSING_ERR(sconf->floating, "Floating point decoding", -1);
431  MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", -1);
432  MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
433 
434  return error;
435 }
436 
437 
441 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
442  unsigned int div, unsigned int **div_blocks,
443  unsigned int *num_blocks)
444 {
445  if (n < 31 && ((bs_info << n) & 0x40000000)) {
446  // if the level is valid and the investigated bit n is set
447  // then recursively check both children at bits (2n+1) and (2n+2)
448  n *= 2;
449  div += 1;
450  parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
451  parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
452  } else {
453  // else the bit is not set or the last level has been reached
454  // (bit implicitly not set)
455  **div_blocks = div;
456  (*div_blocks)++;
457  (*num_blocks)++;
458  }
459 }
460 
461 
464 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
465 {
466  int max = get_bits_left(gb) - k;
467  int q = get_unary(gb, 0, max);
468  int r = k ? get_bits1(gb) : !(q & 1);
469 
470  if (k > 1) {
471  q <<= (k - 1);
472  q += get_bits_long(gb, k - 1);
473  } else if (!k) {
474  q >>= 1;
475  }
476  return r ? q : ~q;
477 }
478 
479 
482 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
483 {
484  int i, j;
485 
486  for (i = 0, j = k - 1; i < j; i++, j--) {
487  int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
488  cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
489  cof[i] += tmp1;
490  }
491  if (i == j)
492  cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
493 
494  cof[k] = par[k];
495 }
496 
497 
502 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
503  uint32_t *bs_info)
504 {
505  ALSSpecificConfig *sconf = &ctx->sconf;
506  GetBitContext *gb = &ctx->gb;
507  unsigned int *ptr_div_blocks = div_blocks;
508  unsigned int b;
509 
510  if (sconf->block_switching) {
511  unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
512  *bs_info = get_bits_long(gb, bs_info_len);
513  *bs_info <<= (32 - bs_info_len);
514  }
515 
516  ctx->num_blocks = 0;
517  parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
518 
519  // The last frame may have an overdetermined block structure given in
520  // the bitstream. In that case the defined block structure would need
521  // more samples than available to be consistent.
522  // The block structure is actually used but the block sizes are adapted
523  // to fit the actual number of available samples.
524  // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
525  // This results in the actual block sizes: 2 2 1 0.
526  // This is not specified in 14496-3 but actually done by the reference
527  // codec RM22 revision 2.
528  // This appears to happen in case of an odd number of samples in the last
529  // frame which is actually not allowed by the block length switching part
530  // of 14496-3.
531  // The ALS conformance files feature an odd number of samples in the last
532  // frame.
533 
534  for (b = 0; b < ctx->num_blocks; b++)
535  div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
536 
537  if (ctx->cur_frame_length != ctx->sconf.frame_length) {
538  unsigned int remaining = ctx->cur_frame_length;
539 
540  for (b = 0; b < ctx->num_blocks; b++) {
541  if (remaining <= div_blocks[b]) {
542  div_blocks[b] = remaining;
543  ctx->num_blocks = b + 1;
544  break;
545  }
546 
547  remaining -= div_blocks[b];
548  }
549  }
550 }
551 
552 
556 {
557  ALSSpecificConfig *sconf = &ctx->sconf;
558  AVCodecContext *avctx = ctx->avctx;
559  GetBitContext *gb = &ctx->gb;
560 
561  *bd->raw_samples = 0;
562  *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
563  bd->js_blocks = get_bits1(gb);
564 
565  // skip 5 reserved bits
566  skip_bits(gb, 5);
567 
568  if (*bd->const_block) {
569  unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
570  *bd->raw_samples = get_sbits_long(gb, const_val_bits);
571  }
572 
573  // ensure constant block decoding by reusing this field
574  *bd->const_block = 1;
575 }
576 
577 
581 {
582  int smp = bd->block_length - 1;
583  int32_t val = *bd->raw_samples;
584  int32_t *dst = bd->raw_samples + 1;
585 
586  // write raw samples into buffer
587  for (; smp; smp--)
588  *dst++ = val;
589 }
590 
591 
595 {
596  ALSSpecificConfig *sconf = &ctx->sconf;
597  AVCodecContext *avctx = ctx->avctx;
598  GetBitContext *gb = &ctx->gb;
599  unsigned int k;
600  unsigned int s[8];
601  unsigned int sx[8];
602  unsigned int sub_blocks, log2_sub_blocks, sb_length;
603  unsigned int start = 0;
604  unsigned int opt_order;
605  int sb;
606  int32_t *quant_cof = bd->quant_cof;
607  int32_t *current_res;
608 
609 
610  // ensure variable block decoding by reusing this field
611  *bd->const_block = 0;
612 
613  *bd->opt_order = 1;
614  bd->js_blocks = get_bits1(gb);
615 
616  opt_order = *bd->opt_order;
617 
618  // determine the number of subblocks for entropy decoding
619  if (!sconf->bgmc && !sconf->sb_part) {
620  log2_sub_blocks = 0;
621  } else {
622  if (sconf->bgmc && sconf->sb_part)
623  log2_sub_blocks = get_bits(gb, 2);
624  else
625  log2_sub_blocks = 2 * get_bits1(gb);
626  }
627 
628  sub_blocks = 1 << log2_sub_blocks;
629 
630  // do not continue in case of a damaged stream since
631  // block_length must be evenly divisible by sub_blocks
632  if (bd->block_length & (sub_blocks - 1)) {
633  av_log(avctx, AV_LOG_WARNING,
634  "Block length is not evenly divisible by the number of subblocks.\n");
635  return -1;
636  }
637 
638  sb_length = bd->block_length >> log2_sub_blocks;
639 
640  if (sconf->bgmc) {
641  s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
642  for (k = 1; k < sub_blocks; k++)
643  s[k] = s[k - 1] + decode_rice(gb, 2);
644 
645  for (k = 0; k < sub_blocks; k++) {
646  sx[k] = s[k] & 0x0F;
647  s [k] >>= 4;
648  }
649  } else {
650  s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
651  for (k = 1; k < sub_blocks; k++)
652  s[k] = s[k - 1] + decode_rice(gb, 0);
653  }
654 
655  if (get_bits1(gb))
656  *bd->shift_lsbs = get_bits(gb, 4) + 1;
657 
658  *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
659 
660 
661  if (!sconf->rlslms) {
662  if (sconf->adapt_order) {
663  int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
664  2, sconf->max_order + 1));
665  *bd->opt_order = get_bits(gb, opt_order_length);
666  } else {
667  *bd->opt_order = sconf->max_order;
668  }
669 
670  opt_order = *bd->opt_order;
671 
672  if (opt_order) {
673  int add_base;
674 
675  if (sconf->coef_table == 3) {
676  add_base = 0x7F;
677 
678  // read coefficient 0
679  quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
680 
681  // read coefficient 1
682  if (opt_order > 1)
683  quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
684 
685  // read coefficients 2 to opt_order
686  for (k = 2; k < opt_order; k++)
687  quant_cof[k] = get_bits(gb, 7);
688  } else {
689  int k_max;
690  add_base = 1;
691 
692  // read coefficient 0 to 19
693  k_max = FFMIN(opt_order, 20);
694  for (k = 0; k < k_max; k++) {
695  int rice_param = parcor_rice_table[sconf->coef_table][k][1];
696  int offset = parcor_rice_table[sconf->coef_table][k][0];
697  quant_cof[k] = decode_rice(gb, rice_param) + offset;
698  }
699 
700  // read coefficients 20 to 126
701  k_max = FFMIN(opt_order, 127);
702  for (; k < k_max; k++)
703  quant_cof[k] = decode_rice(gb, 2) + (k & 1);
704 
705  // read coefficients 127 to opt_order
706  for (; k < opt_order; k++)
707  quant_cof[k] = decode_rice(gb, 1);
708 
709  quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
710 
711  if (opt_order > 1)
712  quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
713  }
714 
715  for (k = 2; k < opt_order; k++)
716  quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
717  }
718  }
719 
720  // read LTP gain and lag values
721  if (sconf->long_term_prediction) {
722  *bd->use_ltp = get_bits1(gb);
723 
724  if (*bd->use_ltp) {
725  int r, c;
726 
727  bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
728  bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
729 
730  r = get_unary(gb, 0, 4);
731  c = get_bits(gb, 2);
732  bd->ltp_gain[2] = ltp_gain_values[r][c];
733 
734  bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
735  bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
736 
737  *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
738  *bd->ltp_lag += FFMAX(4, opt_order + 1);
739  }
740  }
741 
742  // read first value and residuals in case of a random access block
743  if (bd->ra_block) {
744  if (opt_order)
745  bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
746  if (opt_order > 1)
747  bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
748  if (opt_order > 2)
749  bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
750 
751  start = FFMIN(opt_order, 3);
752  }
753 
754  // read all residuals
755  if (sconf->bgmc) {
756  int delta[8];
757  unsigned int k [8];
758  unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
759  unsigned int i = start;
760 
761  // read most significant bits
762  unsigned int high;
763  unsigned int low;
764  unsigned int value;
765 
766  ff_bgmc_decode_init(gb, &high, &low, &value);
767 
768  current_res = bd->raw_samples + start;
769 
770  for (sb = 0; sb < sub_blocks; sb++, i = 0) {
771  k [sb] = s[sb] > b ? s[sb] - b : 0;
772  delta[sb] = 5 - s[sb] + k[sb];
773 
774  ff_bgmc_decode(gb, sb_length, current_res,
775  delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
776 
777  current_res += sb_length;
778  }
779 
780  ff_bgmc_decode_end(gb);
781 
782 
783  // read least significant bits and tails
784  i = start;
785  current_res = bd->raw_samples + start;
786 
787  for (sb = 0; sb < sub_blocks; sb++, i = 0) {
788  unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
789  unsigned int cur_k = k[sb];
790  unsigned int cur_s = s[sb];
791 
792  for (; i < sb_length; i++) {
793  int32_t res = *current_res;
794 
795  if (res == cur_tail_code) {
796  unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
797  << (5 - delta[sb]);
798 
799  res = decode_rice(gb, cur_s);
800 
801  if (res >= 0) {
802  res += (max_msb ) << cur_k;
803  } else {
804  res -= (max_msb - 1) << cur_k;
805  }
806  } else {
807  if (res > cur_tail_code)
808  res--;
809 
810  if (res & 1)
811  res = -res;
812 
813  res >>= 1;
814 
815  if (cur_k) {
816  res <<= cur_k;
817  res |= get_bits_long(gb, cur_k);
818  }
819  }
820 
821  *current_res++ = res;
822  }
823  }
824  } else {
825  current_res = bd->raw_samples + start;
826 
827  for (sb = 0; sb < sub_blocks; sb++, start = 0)
828  for (; start < sb_length; start++)
829  *current_res++ = decode_rice(gb, s[sb]);
830  }
831 
832  if (!sconf->mc_coding || ctx->js_switch)
833  align_get_bits(gb);
834 
835  return 0;
836 }
837 
838 
842 {
843  ALSSpecificConfig *sconf = &ctx->sconf;
844  unsigned int block_length = bd->block_length;
845  unsigned int smp = 0;
846  unsigned int k;
847  int opt_order = *bd->opt_order;
848  int sb;
849  int64_t y;
850  int32_t *quant_cof = bd->quant_cof;
851  int32_t *lpc_cof = bd->lpc_cof;
852  int32_t *raw_samples = bd->raw_samples;
853  int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
854  int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
855 
856  // reverse long-term prediction
857  if (*bd->use_ltp) {
858  int ltp_smp;
859 
860  for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
861  int center = ltp_smp - *bd->ltp_lag;
862  int begin = FFMAX(0, center - 2);
863  int end = center + 3;
864  int tab = 5 - (end - begin);
865  int base;
866 
867  y = 1 << 6;
868 
869  for (base = begin; base < end; base++, tab++)
870  y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
871 
872  raw_samples[ltp_smp] += y >> 7;
873  }
874  }
875 
876  // reconstruct all samples from residuals
877  if (bd->ra_block) {
878  for (smp = 0; smp < opt_order; smp++) {
879  y = 1 << 19;
880 
881  for (sb = 0; sb < smp; sb++)
882  y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
883 
884  *raw_samples++ -= y >> 20;
885  parcor_to_lpc(smp, quant_cof, lpc_cof);
886  }
887  } else {
888  for (k = 0; k < opt_order; k++)
889  parcor_to_lpc(k, quant_cof, lpc_cof);
890 
891  // store previous samples in case that they have to be altered
892  if (*bd->store_prev_samples)
893  memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
894  sizeof(*bd->prev_raw_samples) * sconf->max_order);
895 
896  // reconstruct difference signal for prediction (joint-stereo)
897  if (bd->js_blocks && bd->raw_other) {
898  int32_t *left, *right;
899 
900  if (bd->raw_other > raw_samples) { // D = R - L
901  left = raw_samples;
902  right = bd->raw_other;
903  } else { // D = R - L
904  left = bd->raw_other;
905  right = raw_samples;
906  }
907 
908  for (sb = -1; sb >= -sconf->max_order; sb--)
909  raw_samples[sb] = right[sb] - left[sb];
910  }
911 
912  // reconstruct shifted signal
913  if (*bd->shift_lsbs)
914  for (sb = -1; sb >= -sconf->max_order; sb--)
915  raw_samples[sb] >>= *bd->shift_lsbs;
916  }
917 
918  // reverse linear prediction coefficients for efficiency
919  lpc_cof = lpc_cof + opt_order;
920 
921  for (sb = 0; sb < opt_order; sb++)
922  lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
923 
924  // reconstruct raw samples
925  raw_samples = bd->raw_samples + smp;
926  lpc_cof = lpc_cof_reversed + opt_order;
927 
928  for (; raw_samples < raw_samples_end; raw_samples++) {
929  y = 1 << 19;
930 
931  for (sb = -opt_order; sb < 0; sb++)
932  y += MUL64(lpc_cof[sb], raw_samples[sb]);
933 
934  *raw_samples -= y >> 20;
935  }
936 
937  raw_samples = bd->raw_samples;
938 
939  // restore previous samples in case that they have been altered
940  if (*bd->store_prev_samples)
941  memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
942  sizeof(*raw_samples) * sconf->max_order);
943 
944  return 0;
945 }
946 
947 
950 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
951 {
952  GetBitContext *gb = &ctx->gb;
953 
954  *bd->shift_lsbs = 0;
955  // read block type flag and read the samples accordingly
956  if (get_bits1(gb)) {
957  if (read_var_block_data(ctx, bd))
958  return -1;
959  } else {
960  read_const_block_data(ctx, bd);
961  }
962 
963  return 0;
964 }
965 
966 
970 {
971  unsigned int smp;
972 
973  // read block type flag and read the samples accordingly
974  if (*bd->const_block)
975  decode_const_block_data(ctx, bd);
976  else if (decode_var_block_data(ctx, bd))
977  return -1;
978 
979  // TODO: read RLSLMS extension data
980 
981  if (*bd->shift_lsbs)
982  for (smp = 0; smp < bd->block_length; smp++)
983  bd->raw_samples[smp] <<= *bd->shift_lsbs;
984 
985  return 0;
986 }
987 
988 
992 {
993  int ret;
994 
995  ret = read_block(ctx, bd);
996 
997  if (ret)
998  return ret;
999 
1000  ret = decode_block(ctx, bd);
1001 
1002  return ret;
1003 }
1004 
1005 
1009 static void zero_remaining(unsigned int b, unsigned int b_max,
1010  const unsigned int *div_blocks, int32_t *buf)
1011 {
1012  unsigned int count = 0;
1013 
1014  for (; b < b_max; b++)
1015  count += div_blocks[b];
1016 
1017  if (count)
1018  memset(buf, 0, sizeof(*buf) * count);
1019 }
1020 
1021 
1024 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1025  unsigned int c, const unsigned int *div_blocks,
1026  unsigned int *js_blocks)
1027 {
1028  unsigned int b;
1029  ALSBlockData bd;
1030 
1031  memset(&bd, 0, sizeof(ALSBlockData));
1032 
1033  bd.ra_block = ra_frame;
1034  bd.const_block = ctx->const_block;
1035  bd.shift_lsbs = ctx->shift_lsbs;
1036  bd.opt_order = ctx->opt_order;
1038  bd.use_ltp = ctx->use_ltp;
1039  bd.ltp_lag = ctx->ltp_lag;
1040  bd.ltp_gain = ctx->ltp_gain[0];
1041  bd.quant_cof = ctx->quant_cof[0];
1042  bd.lpc_cof = ctx->lpc_cof[0];
1044  bd.raw_samples = ctx->raw_samples[c];
1045 
1046 
1047  for (b = 0; b < ctx->num_blocks; b++) {
1048  bd.block_length = div_blocks[b];
1049 
1050  if (read_decode_block(ctx, &bd)) {
1051  // damaged block, write zero for the rest of the frame
1052  zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1053  return -1;
1054  }
1055  bd.raw_samples += div_blocks[b];
1056  bd.ra_block = 0;
1057  }
1058 
1059  return 0;
1060 }
1061 
1062 
1065 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1066  unsigned int c, const unsigned int *div_blocks,
1067  unsigned int *js_blocks)
1068 {
1069  ALSSpecificConfig *sconf = &ctx->sconf;
1070  unsigned int offset = 0;
1071  unsigned int b;
1072  ALSBlockData bd[2];
1073 
1074  memset(bd, 0, 2 * sizeof(ALSBlockData));
1075 
1076  bd[0].ra_block = ra_frame;
1077  bd[0].const_block = ctx->const_block;
1078  bd[0].shift_lsbs = ctx->shift_lsbs;
1079  bd[0].opt_order = ctx->opt_order;
1081  bd[0].use_ltp = ctx->use_ltp;
1082  bd[0].ltp_lag = ctx->ltp_lag;
1083  bd[0].ltp_gain = ctx->ltp_gain[0];
1084  bd[0].quant_cof = ctx->quant_cof[0];
1085  bd[0].lpc_cof = ctx->lpc_cof[0];
1086  bd[0].prev_raw_samples = ctx->prev_raw_samples;
1087  bd[0].js_blocks = *js_blocks;
1088 
1089  bd[1].ra_block = ra_frame;
1090  bd[1].const_block = ctx->const_block;
1091  bd[1].shift_lsbs = ctx->shift_lsbs;
1092  bd[1].opt_order = ctx->opt_order;
1094  bd[1].use_ltp = ctx->use_ltp;
1095  bd[1].ltp_lag = ctx->ltp_lag;
1096  bd[1].ltp_gain = ctx->ltp_gain[0];
1097  bd[1].quant_cof = ctx->quant_cof[0];
1098  bd[1].lpc_cof = ctx->lpc_cof[0];
1099  bd[1].prev_raw_samples = ctx->prev_raw_samples;
1100  bd[1].js_blocks = *(js_blocks + 1);
1101 
1102  // decode all blocks
1103  for (b = 0; b < ctx->num_blocks; b++) {
1104  unsigned int s;
1105 
1106  bd[0].block_length = div_blocks[b];
1107  bd[1].block_length = div_blocks[b];
1108 
1109  bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1110  bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1111 
1112  bd[0].raw_other = bd[1].raw_samples;
1113  bd[1].raw_other = bd[0].raw_samples;
1114 
1115  if(read_decode_block(ctx, &bd[0]) || read_decode_block(ctx, &bd[1])) {
1116  // damaged block, write zero for the rest of the frame
1117  zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1118  zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1119  return -1;
1120  }
1121 
1122  // reconstruct joint-stereo blocks
1123  if (bd[0].js_blocks) {
1124  if (bd[1].js_blocks)
1125  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair!\n");
1126 
1127  for (s = 0; s < div_blocks[b]; s++)
1128  bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1129  } else if (bd[1].js_blocks) {
1130  for (s = 0; s < div_blocks[b]; s++)
1131  bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1132  }
1133 
1134  offset += div_blocks[b];
1135  bd[0].ra_block = 0;
1136  bd[1].ra_block = 0;
1137  }
1138 
1139  // store carryover raw samples,
1140  // the others channel raw samples are stored by the calling function.
1141  memmove(ctx->raw_samples[c] - sconf->max_order,
1142  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1143  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1144 
1145  return 0;
1146 }
1147 
1148 
1151 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1152 {
1153  GetBitContext *gb = &ctx->gb;
1154  ALSChannelData *current = cd;
1155  unsigned int channels = ctx->avctx->channels;
1156  int entries = 0;
1157 
1158  while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1159  current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1160 
1161  if (current->master_channel >= channels) {
1162  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel!\n");
1163  return -1;
1164  }
1165 
1166  if (current->master_channel != c) {
1167  current->time_diff_flag = get_bits1(gb);
1168  current->weighting[0] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1169  current->weighting[1] = mcc_weightings[av_clip(decode_rice(gb, 2) + 14, 0, 32)];
1170  current->weighting[2] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1171 
1172  if (current->time_diff_flag) {
1173  current->weighting[3] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1174  current->weighting[4] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1175  current->weighting[5] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1176 
1177  current->time_diff_sign = get_bits1(gb);
1178  current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1179  }
1180  }
1181 
1182  current++;
1183  entries++;
1184  }
1185 
1186  if (entries == channels) {
1187  av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data!\n");
1188  return -1;
1189  }
1190 
1191  align_get_bits(gb);
1192  return 0;
1193 }
1194 
1195 
1199  ALSChannelData **cd, int *reverted,
1200  unsigned int offset, int c)
1201 {
1202  ALSChannelData *ch = cd[c];
1203  unsigned int dep = 0;
1204  unsigned int channels = ctx->avctx->channels;
1205 
1206  if (reverted[c])
1207  return 0;
1208 
1209  reverted[c] = 1;
1210 
1211  while (dep < channels && !ch[dep].stop_flag) {
1212  revert_channel_correlation(ctx, bd, cd, reverted, offset,
1213  ch[dep].master_channel);
1214 
1215  dep++;
1216  }
1217 
1218  if (dep == channels) {
1219  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation!\n");
1220  return -1;
1221  }
1222 
1223  bd->const_block = ctx->const_block + c;
1224  bd->shift_lsbs = ctx->shift_lsbs + c;
1225  bd->opt_order = ctx->opt_order + c;
1226  bd->store_prev_samples = ctx->store_prev_samples + c;
1227  bd->use_ltp = ctx->use_ltp + c;
1228  bd->ltp_lag = ctx->ltp_lag + c;
1229  bd->ltp_gain = ctx->ltp_gain[c];
1230  bd->lpc_cof = ctx->lpc_cof[c];
1231  bd->quant_cof = ctx->quant_cof[c];
1232  bd->raw_samples = ctx->raw_samples[c] + offset;
1233 
1234  dep = 0;
1235  while (!ch[dep].stop_flag) {
1236  unsigned int smp;
1237  unsigned int begin = 1;
1238  unsigned int end = bd->block_length - 1;
1239  int64_t y;
1240  int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1241 
1242  if (ch[dep].time_diff_flag) {
1243  int t = ch[dep].time_diff_index;
1244 
1245  if (ch[dep].time_diff_sign) {
1246  t = -t;
1247  begin -= t;
1248  } else {
1249  end -= t;
1250  }
1251 
1252  for (smp = begin; smp < end; smp++) {
1253  y = (1 << 6) +
1254  MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1255  MUL64(ch[dep].weighting[1], master[smp ]) +
1256  MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1257  MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1258  MUL64(ch[dep].weighting[4], master[smp + t]) +
1259  MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1260 
1261  bd->raw_samples[smp] += y >> 7;
1262  }
1263  } else {
1264  for (smp = begin; smp < end; smp++) {
1265  y = (1 << 6) +
1266  MUL64(ch[dep].weighting[0], master[smp - 1]) +
1267  MUL64(ch[dep].weighting[1], master[smp ]) +
1268  MUL64(ch[dep].weighting[2], master[smp + 1]);
1269 
1270  bd->raw_samples[smp] += y >> 7;
1271  }
1272  }
1273 
1274  dep++;
1275  }
1276 
1277  return 0;
1278 }
1279 
1280 
1283 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1284 {
1285  ALSSpecificConfig *sconf = &ctx->sconf;
1286  AVCodecContext *avctx = ctx->avctx;
1287  GetBitContext *gb = &ctx->gb;
1288  unsigned int div_blocks[32];
1289  unsigned int c;
1290  unsigned int js_blocks[2];
1291 
1292  uint32_t bs_info = 0;
1293 
1294  // skip the size of the ra unit if present in the frame
1295  if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1296  skip_bits_long(gb, 32);
1297 
1298  if (sconf->mc_coding && sconf->joint_stereo) {
1299  ctx->js_switch = get_bits1(gb);
1300  align_get_bits(gb);
1301  }
1302 
1303  if (!sconf->mc_coding || ctx->js_switch) {
1304  int independent_bs = !sconf->joint_stereo;
1305 
1306  for (c = 0; c < avctx->channels; c++) {
1307  js_blocks[0] = 0;
1308  js_blocks[1] = 0;
1309 
1310  get_block_sizes(ctx, div_blocks, &bs_info);
1311 
1312  // if joint_stereo and block_switching is set, independent decoding
1313  // is signaled via the first bit of bs_info
1314  if (sconf->joint_stereo && sconf->block_switching)
1315  if (bs_info >> 31)
1316  independent_bs = 2;
1317 
1318  // if this is the last channel, it has to be decoded independently
1319  if (c == avctx->channels - 1)
1320  independent_bs = 1;
1321 
1322  if (independent_bs) {
1323  if (decode_blocks_ind(ctx, ra_frame, c, div_blocks, js_blocks))
1324  return -1;
1325 
1326  independent_bs--;
1327  } else {
1328  if (decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks))
1329  return -1;
1330 
1331  c++;
1332  }
1333 
1334  // store carryover raw samples
1335  memmove(ctx->raw_samples[c] - sconf->max_order,
1336  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1337  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1338  }
1339  } else { // multi-channel coding
1340  ALSBlockData bd;
1341  int b;
1342  int *reverted_channels = ctx->reverted_channels;
1343  unsigned int offset = 0;
1344 
1345  for (c = 0; c < avctx->channels; c++)
1346  if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1347  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data!\n");
1348  return -1;
1349  }
1350 
1351  memset(&bd, 0, sizeof(ALSBlockData));
1352  memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1353 
1354  bd.ra_block = ra_frame;
1356 
1357  get_block_sizes(ctx, div_blocks, &bs_info);
1358 
1359  for (b = 0; b < ctx->num_blocks; b++) {
1360  bd.block_length = div_blocks[b];
1361 
1362  for (c = 0; c < avctx->channels; c++) {
1363  bd.const_block = ctx->const_block + c;
1364  bd.shift_lsbs = ctx->shift_lsbs + c;
1365  bd.opt_order = ctx->opt_order + c;
1366  bd.store_prev_samples = ctx->store_prev_samples + c;
1367  bd.use_ltp = ctx->use_ltp + c;
1368  bd.ltp_lag = ctx->ltp_lag + c;
1369  bd.ltp_gain = ctx->ltp_gain[c];
1370  bd.lpc_cof = ctx->lpc_cof[c];
1371  bd.quant_cof = ctx->quant_cof[c];
1372  bd.raw_samples = ctx->raw_samples[c] + offset;
1373  bd.raw_other = NULL;
1374 
1375  read_block(ctx, &bd);
1376  if (read_channel_data(ctx, ctx->chan_data[c], c))
1377  return -1;
1378  }
1379 
1380  for (c = 0; c < avctx->channels; c++)
1381  if (revert_channel_correlation(ctx, &bd, ctx->chan_data,
1382  reverted_channels, offset, c))
1383  return -1;
1384 
1385  for (c = 0; c < avctx->channels; c++) {
1386  bd.const_block = ctx->const_block + c;
1387  bd.shift_lsbs = ctx->shift_lsbs + c;
1388  bd.opt_order = ctx->opt_order + c;
1389  bd.store_prev_samples = ctx->store_prev_samples + c;
1390  bd.use_ltp = ctx->use_ltp + c;
1391  bd.ltp_lag = ctx->ltp_lag + c;
1392  bd.ltp_gain = ctx->ltp_gain[c];
1393  bd.lpc_cof = ctx->lpc_cof[c];
1394  bd.quant_cof = ctx->quant_cof[c];
1395  bd.raw_samples = ctx->raw_samples[c] + offset;
1396  decode_block(ctx, &bd);
1397  }
1398 
1399  memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1400  offset += div_blocks[b];
1401  bd.ra_block = 0;
1402  }
1403 
1404  // store carryover raw samples
1405  for (c = 0; c < avctx->channels; c++)
1406  memmove(ctx->raw_samples[c] - sconf->max_order,
1407  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1408  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1409  }
1410 
1411  // TODO: read_diff_float_data
1412 
1413  return 0;
1414 }
1415 
1416 
1419 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1420  AVPacket *avpkt)
1421 {
1422  ALSDecContext *ctx = avctx->priv_data;
1423  ALSSpecificConfig *sconf = &ctx->sconf;
1424  const uint8_t *buffer = avpkt->data;
1425  int buffer_size = avpkt->size;
1426  int invalid_frame, ret;
1427  unsigned int c, sample, ra_frame, bytes_read, shift;
1428 
1429  init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1430 
1431  // In the case that the distance between random access frames is set to zero
1432  // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1433  // For the first frame, if prediction is used, all samples used from the
1434  // previous frame are assumed to be zero.
1435  ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1436 
1437  // the last frame to decode might have a different length
1438  if (sconf->samples != 0xFFFFFFFF)
1439  ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1440  sconf->frame_length);
1441  else
1442  ctx->cur_frame_length = sconf->frame_length;
1443 
1444  // decode the frame data
1445  if ((invalid_frame = read_frame_data(ctx, ra_frame) < 0))
1446  av_log(ctx->avctx, AV_LOG_WARNING,
1447  "Reading frame data failed. Skipping RA unit.\n");
1448 
1449  ctx->frame_id++;
1450 
1451  /* get output buffer */
1452  ctx->frame.nb_samples = ctx->cur_frame_length;
1453  if ((ret = avctx->get_buffer(avctx, &ctx->frame)) < 0) {
1454  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
1455  return ret;
1456  }
1457 
1458  // transform decoded frame into output format
1459  #define INTERLEAVE_OUTPUT(bps) \
1460  { \
1461  int##bps##_t *dest = (int##bps##_t*)ctx->frame.data[0]; \
1462  shift = bps - ctx->avctx->bits_per_raw_sample; \
1463  for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1464  for (c = 0; c < avctx->channels; c++) \
1465  *dest++ = ctx->raw_samples[c][sample] << shift; \
1466  }
1467 
1468  if (ctx->avctx->bits_per_raw_sample <= 16) {
1469  INTERLEAVE_OUTPUT(16)
1470  } else {
1471  INTERLEAVE_OUTPUT(32)
1472  }
1473 
1474  // update CRC
1475  if (sconf->crc_enabled && (avctx->err_recognition & AV_EF_CRCCHECK)) {
1476  int swap = HAVE_BIGENDIAN != sconf->msb_first;
1477 
1478  if (ctx->avctx->bits_per_raw_sample == 24) {
1479  int32_t *src = (int32_t *)ctx->frame.data[0];
1480 
1481  for (sample = 0;
1482  sample < ctx->cur_frame_length * avctx->channels;
1483  sample++) {
1484  int32_t v;
1485 
1486  if (swap)
1487  v = av_bswap32(src[sample]);
1488  else
1489  v = src[sample];
1490  if (!HAVE_BIGENDIAN)
1491  v >>= 8;
1492 
1493  ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1494  }
1495  } else {
1496  uint8_t *crc_source;
1497 
1498  if (swap) {
1499  if (ctx->avctx->bits_per_raw_sample <= 16) {
1500  int16_t *src = (int16_t*) ctx->frame.data[0];
1501  int16_t *dest = (int16_t*) ctx->crc_buffer;
1502  for (sample = 0;
1503  sample < ctx->cur_frame_length * avctx->channels;
1504  sample++)
1505  *dest++ = av_bswap16(src[sample]);
1506  } else {
1507  ctx->dsp.bswap_buf((uint32_t*)ctx->crc_buffer,
1508  (uint32_t *)ctx->frame.data[0],
1509  ctx->cur_frame_length * avctx->channels);
1510  }
1511  crc_source = ctx->crc_buffer;
1512  } else {
1513  crc_source = ctx->frame.data[0];
1514  }
1515 
1516  ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1517  ctx->cur_frame_length * avctx->channels *
1519  }
1520 
1521 
1522  // check CRC sums if this is the last frame
1523  if (ctx->cur_frame_length != sconf->frame_length &&
1524  ctx->crc_org != ctx->crc) {
1525  av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1526  }
1527  }
1528 
1529  *got_frame_ptr = 1;
1530  *(AVFrame *)data = ctx->frame;
1531 
1532 
1533  bytes_read = invalid_frame ? buffer_size :
1534  (get_bits_count(&ctx->gb) + 7) >> 3;
1535 
1536  return bytes_read;
1537 }
1538 
1539 
1543 {
1544  ALSDecContext *ctx = avctx->priv_data;
1545 
1546  av_freep(&ctx->sconf.chan_pos);
1547 
1548  ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1549 
1550  av_freep(&ctx->const_block);
1551  av_freep(&ctx->shift_lsbs);
1552  av_freep(&ctx->opt_order);
1554  av_freep(&ctx->use_ltp);
1555  av_freep(&ctx->ltp_lag);
1556  av_freep(&ctx->ltp_gain);
1557  av_freep(&ctx->ltp_gain_buffer);
1558  av_freep(&ctx->quant_cof);
1559  av_freep(&ctx->lpc_cof);
1560  av_freep(&ctx->quant_cof_buffer);
1561  av_freep(&ctx->lpc_cof_buffer);
1563  av_freep(&ctx->prev_raw_samples);
1564  av_freep(&ctx->raw_samples);
1565  av_freep(&ctx->raw_buffer);
1566  av_freep(&ctx->chan_data);
1567  av_freep(&ctx->chan_data_buffer);
1568  av_freep(&ctx->reverted_channels);
1569  av_freep(&ctx->crc_buffer);
1570 
1571  return 0;
1572 }
1573 
1574 
1578 {
1579  unsigned int c;
1580  unsigned int channel_size;
1581  int num_buffers;
1582  ALSDecContext *ctx = avctx->priv_data;
1583  ALSSpecificConfig *sconf = &ctx->sconf;
1584  ctx->avctx = avctx;
1585 
1586  if (!avctx->extradata) {
1587  av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1588  return -1;
1589  }
1590 
1591  if (read_specific_config(ctx)) {
1592  av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1593  decode_end(avctx);
1594  return -1;
1595  }
1596 
1597  if (check_specific_config(ctx)) {
1598  decode_end(avctx);
1599  return -1;
1600  }
1601 
1602  if (sconf->bgmc)
1603  ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1604 
1605  if (sconf->floating) {
1606  avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1607  avctx->bits_per_raw_sample = 32;
1608  } else {
1609  avctx->sample_fmt = sconf->resolution > 1
1611  avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1612  }
1613 
1614  // set maximum Rice parameter for progressive decoding based on resolution
1615  // This is not specified in 14496-3 but actually done by the reference
1616  // codec RM22 revision 2.
1617  ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1618 
1619  // set lag value for long-term prediction
1620  ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1621  (avctx->sample_rate >= 192000);
1622 
1623  // allocate quantized parcor coefficient buffer
1624  num_buffers = sconf->mc_coding ? avctx->channels : 1;
1625 
1626  ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1627  ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1628  ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1629  num_buffers * sconf->max_order);
1630  ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1631  num_buffers * sconf->max_order);
1632  ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1633  sconf->max_order);
1634 
1635  if (!ctx->quant_cof || !ctx->lpc_cof ||
1636  !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1637  !ctx->lpc_cof_reversed_buffer) {
1638  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1639  return AVERROR(ENOMEM);
1640  }
1641 
1642  // assign quantized parcor coefficient buffers
1643  for (c = 0; c < num_buffers; c++) {
1644  ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1645  ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1646  }
1647 
1648  // allocate and assign lag and gain data buffer for ltp mode
1649  ctx->const_block = av_malloc (sizeof(*ctx->const_block) * num_buffers);
1650  ctx->shift_lsbs = av_malloc (sizeof(*ctx->shift_lsbs) * num_buffers);
1651  ctx->opt_order = av_malloc (sizeof(*ctx->opt_order) * num_buffers);
1652  ctx->store_prev_samples = av_malloc(sizeof(*ctx->store_prev_samples) * num_buffers);
1653  ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1654  ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1655  ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1656  ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1657  num_buffers * 5);
1658 
1659  if (!ctx->const_block || !ctx->shift_lsbs ||
1660  !ctx->opt_order || !ctx->store_prev_samples ||
1661  !ctx->use_ltp || !ctx->ltp_lag ||
1662  !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1663  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1664  decode_end(avctx);
1665  return AVERROR(ENOMEM);
1666  }
1667 
1668  for (c = 0; c < num_buffers; c++)
1669  ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1670 
1671  // allocate and assign channel data buffer for mcc mode
1672  if (sconf->mc_coding) {
1673  ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1674  num_buffers * num_buffers);
1675  ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) *
1676  num_buffers);
1677  ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1678  num_buffers);
1679 
1680  if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1681  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1682  decode_end(avctx);
1683  return AVERROR(ENOMEM);
1684  }
1685 
1686  for (c = 0; c < num_buffers; c++)
1687  ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
1688  } else {
1689  ctx->chan_data = NULL;
1690  ctx->chan_data_buffer = NULL;
1691  ctx->reverted_channels = NULL;
1692  }
1693 
1694  avctx->frame_size = sconf->frame_length;
1695  channel_size = sconf->frame_length + sconf->max_order;
1696 
1697  ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1698  ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1699  ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1700 
1701  // allocate previous raw sample buffer
1702  if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1703  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1704  decode_end(avctx);
1705  return AVERROR(ENOMEM);
1706  }
1707 
1708  // assign raw samples buffers
1709  ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1710  for (c = 1; c < avctx->channels; c++)
1711  ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1712 
1713  // allocate crc buffer
1714  if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
1715  (avctx->err_recognition & AV_EF_CRCCHECK)) {
1716  ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) *
1717  ctx->cur_frame_length *
1718  avctx->channels *
1720  if (!ctx->crc_buffer) {
1721  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1722  decode_end(avctx);
1723  return AVERROR(ENOMEM);
1724  }
1725  }
1726 
1727  dsputil_init(&ctx->dsp, avctx);
1728 
1730  avctx->coded_frame = &ctx->frame;
1731 
1732  return 0;
1733 }
1734 
1735 
1738 static av_cold void flush(AVCodecContext *avctx)
1739 {
1740  ALSDecContext *ctx = avctx->priv_data;
1741 
1742  ctx->frame_id = 0;
1743 }
1744 
1745 
1747  .name = "als",
1748  .type = AVMEDIA_TYPE_AUDIO,
1749  .id = CODEC_ID_MP4ALS,
1750  .priv_data_size = sizeof(ALSDecContext),
1751  .init = decode_init,
1752  .close = decode_end,
1753  .decode = decode_frame,
1754  .flush = flush,
1755  .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
1756  .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),
1757 };
1758