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;
163  enum RA_Flag ra_flag;
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 AVERROR_INVALIDDATA;
298 
299  skip_bits_long(&gb, config_offset);
300 
301  if (get_bits_left(&gb) < (30 << 3))
302  return AVERROR_INVALIDDATA;
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 AVERROR_INVALIDDATA;
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 AVERROR_INVALIDDATA;
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 AVERROR_INVALIDDATA;
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 AVERROR_INVALIDDATA;
385 
386  if (ht_size > INT32_MAX)
387  return AVERROR_PATCHWELCOME;
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 AVERROR_INVALIDDATA;
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 AVERROR_INVALIDDATA;
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  for (k = 1; k < sub_blocks; k++)
655  if (s[k] > 32) {
656  av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n");
657  return AVERROR_INVALIDDATA;
658  }
659 
660  if (get_bits1(gb))
661  *bd->shift_lsbs = get_bits(gb, 4) + 1;
662 
663  *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
664 
665 
666  if (!sconf->rlslms) {
667  if (sconf->adapt_order) {
668  int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
669  2, sconf->max_order + 1));
670  *bd->opt_order = get_bits(gb, opt_order_length);
671  if (*bd->opt_order > sconf->max_order) {
672  *bd->opt_order = sconf->max_order;
673  av_log(avctx, AV_LOG_ERROR, "Predictor order too large!\n");
674  return AVERROR_INVALIDDATA;
675  }
676  } else {
677  *bd->opt_order = sconf->max_order;
678  }
679 
680  opt_order = *bd->opt_order;
681 
682  if (opt_order) {
683  int add_base;
684 
685  if (sconf->coef_table == 3) {
686  add_base = 0x7F;
687 
688  // read coefficient 0
689  quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
690 
691  // read coefficient 1
692  if (opt_order > 1)
693  quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
694 
695  // read coefficients 2 to opt_order
696  for (k = 2; k < opt_order; k++)
697  quant_cof[k] = get_bits(gb, 7);
698  } else {
699  int k_max;
700  add_base = 1;
701 
702  // read coefficient 0 to 19
703  k_max = FFMIN(opt_order, 20);
704  for (k = 0; k < k_max; k++) {
705  int rice_param = parcor_rice_table[sconf->coef_table][k][1];
706  int offset = parcor_rice_table[sconf->coef_table][k][0];
707  quant_cof[k] = decode_rice(gb, rice_param) + offset;
708  if (quant_cof[k] < -64 || quant_cof[k] > 63) {
709  av_log(avctx, AV_LOG_ERROR, "quant_cof %d is out of range\n", quant_cof[k]);
710  return AVERROR_INVALIDDATA;
711  }
712  }
713 
714  // read coefficients 20 to 126
715  k_max = FFMIN(opt_order, 127);
716  for (; k < k_max; k++)
717  quant_cof[k] = decode_rice(gb, 2) + (k & 1);
718 
719  // read coefficients 127 to opt_order
720  for (; k < opt_order; k++)
721  quant_cof[k] = decode_rice(gb, 1);
722 
723  quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
724 
725  if (opt_order > 1)
726  quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
727  }
728 
729  for (k = 2; k < opt_order; k++)
730  quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
731  }
732  }
733 
734  // read LTP gain and lag values
735  if (sconf->long_term_prediction) {
736  *bd->use_ltp = get_bits1(gb);
737 
738  if (*bd->use_ltp) {
739  int r, c;
740 
741  bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
742  bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
743 
744  r = get_unary(gb, 0, 3);
745  c = get_bits(gb, 2);
746  bd->ltp_gain[2] = ltp_gain_values[r][c];
747 
748  bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
749  bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
750 
751  *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
752  *bd->ltp_lag += FFMAX(4, opt_order + 1);
753  }
754  }
755 
756  // read first value and residuals in case of a random access block
757  if (bd->ra_block) {
758  if (opt_order)
759  bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
760  if (opt_order > 1)
761  bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
762  if (opt_order > 2)
763  bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
764 
765  start = FFMIN(opt_order, 3);
766  }
767 
768  // read all residuals
769  if (sconf->bgmc) {
770  int delta[8];
771  unsigned int k [8];
772  unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
773 
774  // read most significant bits
775  unsigned int high;
776  unsigned int low;
777  unsigned int value;
778 
779  ff_bgmc_decode_init(gb, &high, &low, &value);
780 
781  current_res = bd->raw_samples + start;
782 
783  for (sb = 0; sb < sub_blocks; sb++) {
784  unsigned int sb_len = sb_length - (sb ? 0 : start);
785 
786  k [sb] = s[sb] > b ? s[sb] - b : 0;
787  delta[sb] = 5 - s[sb] + k[sb];
788 
789  ff_bgmc_decode(gb, sb_len, current_res,
790  delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
791 
792  current_res += sb_len;
793  }
794 
795  ff_bgmc_decode_end(gb);
796 
797 
798  // read least significant bits and tails
799  current_res = bd->raw_samples + start;
800 
801  for (sb = 0; sb < sub_blocks; sb++, start = 0) {
802  unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
803  unsigned int cur_k = k[sb];
804  unsigned int cur_s = s[sb];
805 
806  for (; start < sb_length; start++) {
807  int32_t res = *current_res;
808 
809  if (res == cur_tail_code) {
810  unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
811  << (5 - delta[sb]);
812 
813  res = decode_rice(gb, cur_s);
814 
815  if (res >= 0) {
816  res += (max_msb ) << cur_k;
817  } else {
818  res -= (max_msb - 1) << cur_k;
819  }
820  } else {
821  if (res > cur_tail_code)
822  res--;
823 
824  if (res & 1)
825  res = -res;
826 
827  res >>= 1;
828 
829  if (cur_k) {
830  res <<= cur_k;
831  res |= get_bits_long(gb, cur_k);
832  }
833  }
834 
835  *current_res++ = res;
836  }
837  }
838  } else {
839  current_res = bd->raw_samples + start;
840 
841  for (sb = 0; sb < sub_blocks; sb++, start = 0)
842  for (; start < sb_length; start++)
843  *current_res++ = decode_rice(gb, s[sb]);
844  }
845 
846  if (!sconf->mc_coding || ctx->js_switch)
847  align_get_bits(gb);
848 
849  return 0;
850 }
851 
852 
856 {
857  ALSSpecificConfig *sconf = &ctx->sconf;
858  unsigned int block_length = bd->block_length;
859  unsigned int smp = 0;
860  unsigned int k;
861  int opt_order = *bd->opt_order;
862  int sb;
863  int64_t y;
864  int32_t *quant_cof = bd->quant_cof;
865  int32_t *lpc_cof = bd->lpc_cof;
866  int32_t *raw_samples = bd->raw_samples;
867  int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
868  int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
869 
870  // reverse long-term prediction
871  if (*bd->use_ltp) {
872  int ltp_smp;
873 
874  for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
875  int center = ltp_smp - *bd->ltp_lag;
876  int begin = FFMAX(0, center - 2);
877  int end = center + 3;
878  int tab = 5 - (end - begin);
879  int base;
880 
881  y = 1 << 6;
882 
883  for (base = begin; base < end; base++, tab++)
884  y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
885 
886  raw_samples[ltp_smp] += y >> 7;
887  }
888  }
889 
890  // reconstruct all samples from residuals
891  if (bd->ra_block) {
892  for (smp = 0; smp < opt_order; smp++) {
893  y = 1 << 19;
894 
895  for (sb = 0; sb < smp; sb++)
896  y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
897 
898  *raw_samples++ -= y >> 20;
899  parcor_to_lpc(smp, quant_cof, lpc_cof);
900  }
901  } else {
902  for (k = 0; k < opt_order; k++)
903  parcor_to_lpc(k, quant_cof, lpc_cof);
904 
905  // store previous samples in case that they have to be altered
906  if (*bd->store_prev_samples)
907  memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
908  sizeof(*bd->prev_raw_samples) * sconf->max_order);
909 
910  // reconstruct difference signal for prediction (joint-stereo)
911  if (bd->js_blocks && bd->raw_other) {
912  int32_t *left, *right;
913 
914  if (bd->raw_other > raw_samples) { // D = R - L
915  left = raw_samples;
916  right = bd->raw_other;
917  } else { // D = R - L
918  left = bd->raw_other;
919  right = raw_samples;
920  }
921 
922  for (sb = -1; sb >= -sconf->max_order; sb--)
923  raw_samples[sb] = right[sb] - left[sb];
924  }
925 
926  // reconstruct shifted signal
927  if (*bd->shift_lsbs)
928  for (sb = -1; sb >= -sconf->max_order; sb--)
929  raw_samples[sb] >>= *bd->shift_lsbs;
930  }
931 
932  // reverse linear prediction coefficients for efficiency
933  lpc_cof = lpc_cof + opt_order;
934 
935  for (sb = 0; sb < opt_order; sb++)
936  lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
937 
938  // reconstruct raw samples
939  raw_samples = bd->raw_samples + smp;
940  lpc_cof = lpc_cof_reversed + opt_order;
941 
942  for (; raw_samples < raw_samples_end; raw_samples++) {
943  y = 1 << 19;
944 
945  for (sb = -opt_order; sb < 0; sb++)
946  y += MUL64(lpc_cof[sb], raw_samples[sb]);
947 
948  *raw_samples -= y >> 20;
949  }
950 
951  raw_samples = bd->raw_samples;
952 
953  // restore previous samples in case that they have been altered
954  if (*bd->store_prev_samples)
955  memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
956  sizeof(*raw_samples) * sconf->max_order);
957 
958  return 0;
959 }
960 
961 
964 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
965 {
966  int ret = 0;
967  GetBitContext *gb = &ctx->gb;
968 
969  *bd->shift_lsbs = 0;
970  // read block type flag and read the samples accordingly
971  if (get_bits1(gb)) {
972  ret = read_var_block_data(ctx, bd);
973  } else {
974  read_const_block_data(ctx, bd);
975  }
976 
977  return ret;
978 }
979 
980 
984 {
985  unsigned int smp;
986  int ret = 0;
987 
988  // read block type flag and read the samples accordingly
989  if (*bd->const_block)
990  decode_const_block_data(ctx, bd);
991  else
992  ret = decode_var_block_data(ctx, bd); // always return 0
993 
994  if (ret < 0)
995  return ret;
996 
997  // TODO: read RLSLMS extension data
998 
999  if (*bd->shift_lsbs)
1000  for (smp = 0; smp < bd->block_length; smp++)
1001  bd->raw_samples[smp] <<= *bd->shift_lsbs;
1002 
1003  return 0;
1004 }
1005 
1006 
1010 {
1011  int ret;
1012 
1013  if ((ret = read_block(ctx, bd)) < 0)
1014  return ret;
1015 
1016  return decode_block(ctx, bd);
1017 }
1018 
1019 
1023 static void zero_remaining(unsigned int b, unsigned int b_max,
1024  const unsigned int *div_blocks, int32_t *buf)
1025 {
1026  unsigned int count = 0;
1027 
1028  for (; b < b_max; b++)
1029  count += div_blocks[b];
1030 
1031  if (count)
1032  memset(buf, 0, sizeof(*buf) * count);
1033 }
1034 
1035 
1038 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1039  unsigned int c, const unsigned int *div_blocks,
1040  unsigned int *js_blocks)
1041 {
1042  int ret;
1043  unsigned int b;
1044  ALSBlockData bd;
1045 
1046  memset(&bd, 0, sizeof(ALSBlockData));
1047 
1048  bd.ra_block = ra_frame;
1049  bd.const_block = ctx->const_block;
1050  bd.shift_lsbs = ctx->shift_lsbs;
1051  bd.opt_order = ctx->opt_order;
1053  bd.use_ltp = ctx->use_ltp;
1054  bd.ltp_lag = ctx->ltp_lag;
1055  bd.ltp_gain = ctx->ltp_gain[0];
1056  bd.quant_cof = ctx->quant_cof[0];
1057  bd.lpc_cof = ctx->lpc_cof[0];
1059  bd.raw_samples = ctx->raw_samples[c];
1060 
1061 
1062  for (b = 0; b < ctx->num_blocks; b++) {
1063  bd.block_length = div_blocks[b];
1064 
1065  if ((ret = read_decode_block(ctx, &bd)) < 0) {
1066  // damaged block, write zero for the rest of the frame
1067  zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1068  return ret;
1069  }
1070  bd.raw_samples += div_blocks[b];
1071  bd.ra_block = 0;
1072  }
1073 
1074  return 0;
1075 }
1076 
1077 
1080 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1081  unsigned int c, const unsigned int *div_blocks,
1082  unsigned int *js_blocks)
1083 {
1084  ALSSpecificConfig *sconf = &ctx->sconf;
1085  unsigned int offset = 0;
1086  unsigned int b;
1087  int ret;
1088  ALSBlockData bd[2];
1089 
1090  memset(bd, 0, 2 * sizeof(ALSBlockData));
1091 
1092  bd[0].ra_block = ra_frame;
1093  bd[0].const_block = ctx->const_block;
1094  bd[0].shift_lsbs = ctx->shift_lsbs;
1095  bd[0].opt_order = ctx->opt_order;
1097  bd[0].use_ltp = ctx->use_ltp;
1098  bd[0].ltp_lag = ctx->ltp_lag;
1099  bd[0].ltp_gain = ctx->ltp_gain[0];
1100  bd[0].quant_cof = ctx->quant_cof[0];
1101  bd[0].lpc_cof = ctx->lpc_cof[0];
1102  bd[0].prev_raw_samples = ctx->prev_raw_samples;
1103  bd[0].js_blocks = *js_blocks;
1104 
1105  bd[1].ra_block = ra_frame;
1106  bd[1].const_block = ctx->const_block;
1107  bd[1].shift_lsbs = ctx->shift_lsbs;
1108  bd[1].opt_order = ctx->opt_order;
1110  bd[1].use_ltp = ctx->use_ltp;
1111  bd[1].ltp_lag = ctx->ltp_lag;
1112  bd[1].ltp_gain = ctx->ltp_gain[0];
1113  bd[1].quant_cof = ctx->quant_cof[0];
1114  bd[1].lpc_cof = ctx->lpc_cof[0];
1115  bd[1].prev_raw_samples = ctx->prev_raw_samples;
1116  bd[1].js_blocks = *(js_blocks + 1);
1117 
1118  // decode all blocks
1119  for (b = 0; b < ctx->num_blocks; b++) {
1120  unsigned int s;
1121 
1122  bd[0].block_length = div_blocks[b];
1123  bd[1].block_length = div_blocks[b];
1124 
1125  bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1126  bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1127 
1128  bd[0].raw_other = bd[1].raw_samples;
1129  bd[1].raw_other = bd[0].raw_samples;
1130 
1131  if ((ret = read_decode_block(ctx, &bd[0])) < 0 ||
1132  (ret = read_decode_block(ctx, &bd[1])) < 0)
1133  goto fail;
1134 
1135 
1136  // reconstruct joint-stereo blocks
1137  if (bd[0].js_blocks) {
1138  if (bd[1].js_blocks)
1139  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair!\n");
1140 
1141  for (s = 0; s < div_blocks[b]; s++)
1142  bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1143  } else if (bd[1].js_blocks) {
1144  for (s = 0; s < div_blocks[b]; s++)
1145  bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1146  }
1147 
1148  offset += div_blocks[b];
1149  bd[0].ra_block = 0;
1150  bd[1].ra_block = 0;
1151  }
1152 
1153  // store carryover raw samples,
1154  // the others channel raw samples are stored by the calling function.
1155  memmove(ctx->raw_samples[c] - sconf->max_order,
1156  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1157  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1158 
1159  return 0;
1160 fail:
1161  // damaged block, write zero for the rest of the frame
1162  zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1163  zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1164  return ret;
1165 }
1166 
1167 static inline int als_weighting(GetBitContext *gb, int k, int off)
1168 {
1169  int idx = av_clip(decode_rice(gb, k) + off,
1170  0, FF_ARRAY_ELEMS(mcc_weightings) - 1);
1171  return mcc_weightings[idx];
1172 }
1173 
1176 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1177 {
1178  GetBitContext *gb = &ctx->gb;
1179  ALSChannelData *current = cd;
1180  unsigned int channels = ctx->avctx->channels;
1181  int entries = 0;
1182 
1183  while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1184  current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1185 
1186  if (current->master_channel >= channels) {
1187  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel!\n");
1188  return AVERROR_INVALIDDATA;
1189  }
1190 
1191  if (current->master_channel != c) {
1192  current->time_diff_flag = get_bits1(gb);
1193  current->weighting[0] = als_weighting(gb, 1, 16);
1194  current->weighting[1] = als_weighting(gb, 2, 14);
1195  current->weighting[2] = als_weighting(gb, 1, 16);
1196 
1197  if (current->time_diff_flag) {
1198  current->weighting[3] = als_weighting(gb, 1, 16);
1199  current->weighting[4] = als_weighting(gb, 1, 16);
1200  current->weighting[5] = als_weighting(gb, 1, 16);
1201 
1202  current->time_diff_sign = get_bits1(gb);
1203  current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1204  }
1205  }
1206 
1207  current++;
1208  entries++;
1209  }
1210 
1211  if (entries == channels) {
1212  av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data!\n");
1213  return AVERROR_INVALIDDATA;
1214  }
1215 
1216  align_get_bits(gb);
1217  return 0;
1218 }
1219 
1220 
1224  ALSChannelData **cd, int *reverted,
1225  unsigned int offset, int c)
1226 {
1227  ALSChannelData *ch = cd[c];
1228  unsigned int dep = 0;
1229  unsigned int channels = ctx->avctx->channels;
1230 
1231  if (reverted[c])
1232  return 0;
1233 
1234  reverted[c] = 1;
1235 
1236  while (dep < channels && !ch[dep].stop_flag) {
1237  revert_channel_correlation(ctx, bd, cd, reverted, offset,
1238  ch[dep].master_channel);
1239 
1240  dep++;
1241  }
1242 
1243  if (dep == channels) {
1244  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation!\n");
1245  return AVERROR_INVALIDDATA;
1246  }
1247 
1248  bd->const_block = ctx->const_block + c;
1249  bd->shift_lsbs = ctx->shift_lsbs + c;
1250  bd->opt_order = ctx->opt_order + c;
1251  bd->store_prev_samples = ctx->store_prev_samples + c;
1252  bd->use_ltp = ctx->use_ltp + c;
1253  bd->ltp_lag = ctx->ltp_lag + c;
1254  bd->ltp_gain = ctx->ltp_gain[c];
1255  bd->lpc_cof = ctx->lpc_cof[c];
1256  bd->quant_cof = ctx->quant_cof[c];
1257  bd->raw_samples = ctx->raw_samples[c] + offset;
1258 
1259  dep = 0;
1260  while (!ch[dep].stop_flag) {
1261  unsigned int smp;
1262  unsigned int begin = 1;
1263  unsigned int end = bd->block_length - 1;
1264  int64_t y;
1265  int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1266 
1267  if (ch[dep].time_diff_flag) {
1268  int t = ch[dep].time_diff_index;
1269 
1270  if (ch[dep].time_diff_sign) {
1271  t = -t;
1272  begin -= t;
1273  } else {
1274  end -= t;
1275  }
1276 
1277  for (smp = begin; smp < end; smp++) {
1278  y = (1 << 6) +
1279  MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1280  MUL64(ch[dep].weighting[1], master[smp ]) +
1281  MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1282  MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1283  MUL64(ch[dep].weighting[4], master[smp + t]) +
1284  MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1285 
1286  bd->raw_samples[smp] += y >> 7;
1287  }
1288  } else {
1289  for (smp = begin; smp < end; smp++) {
1290  y = (1 << 6) +
1291  MUL64(ch[dep].weighting[0], master[smp - 1]) +
1292  MUL64(ch[dep].weighting[1], master[smp ]) +
1293  MUL64(ch[dep].weighting[2], master[smp + 1]);
1294 
1295  bd->raw_samples[smp] += y >> 7;
1296  }
1297  }
1298 
1299  dep++;
1300  }
1301 
1302  return 0;
1303 }
1304 
1305 
1308 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1309 {
1310  ALSSpecificConfig *sconf = &ctx->sconf;
1311  AVCodecContext *avctx = ctx->avctx;
1312  GetBitContext *gb = &ctx->gb;
1313  unsigned int div_blocks[32];
1314  unsigned int c;
1315  unsigned int js_blocks[2];
1316 
1317  uint32_t bs_info = 0;
1318  int ret;
1319 
1320  // skip the size of the ra unit if present in the frame
1321  if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1322  skip_bits_long(gb, 32);
1323 
1324  if (sconf->mc_coding && sconf->joint_stereo) {
1325  ctx->js_switch = get_bits1(gb);
1326  align_get_bits(gb);
1327  }
1328 
1329  if (!sconf->mc_coding || ctx->js_switch) {
1330  int independent_bs = !sconf->joint_stereo;
1331 
1332  for (c = 0; c < avctx->channels; c++) {
1333  js_blocks[0] = 0;
1334  js_blocks[1] = 0;
1335 
1336  get_block_sizes(ctx, div_blocks, &bs_info);
1337 
1338  // if joint_stereo and block_switching is set, independent decoding
1339  // is signaled via the first bit of bs_info
1340  if (sconf->joint_stereo && sconf->block_switching)
1341  if (bs_info >> 31)
1342  independent_bs = 2;
1343 
1344  // if this is the last channel, it has to be decoded independently
1345  if (c == avctx->channels - 1)
1346  independent_bs = 1;
1347 
1348  if (independent_bs) {
1349  ret = decode_blocks_ind(ctx, ra_frame, c,
1350  div_blocks, js_blocks);
1351  if (ret < 0)
1352  return ret;
1353  independent_bs--;
1354  } else {
1355  ret = decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks);
1356  if (ret < 0)
1357  return ret;
1358 
1359  c++;
1360  }
1361 
1362  // store carryover raw samples
1363  memmove(ctx->raw_samples[c] - sconf->max_order,
1364  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1365  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1366  }
1367  } else { // multi-channel coding
1368  ALSBlockData bd;
1369  int b;
1370  int *reverted_channels = ctx->reverted_channels;
1371  unsigned int offset = 0;
1372 
1373  for (c = 0; c < avctx->channels; c++)
1374  if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1375  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data!\n");
1376  return AVERROR_INVALIDDATA;
1377  }
1378 
1379  memset(&bd, 0, sizeof(ALSBlockData));
1380  memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1381 
1382  bd.ra_block = ra_frame;
1384 
1385  get_block_sizes(ctx, div_blocks, &bs_info);
1386 
1387  for (b = 0; b < ctx->num_blocks; b++) {
1388  bd.block_length = div_blocks[b];
1389 
1390  for (c = 0; c < avctx->channels; c++) {
1391  bd.const_block = ctx->const_block + c;
1392  bd.shift_lsbs = ctx->shift_lsbs + c;
1393  bd.opt_order = ctx->opt_order + c;
1394  bd.store_prev_samples = ctx->store_prev_samples + c;
1395  bd.use_ltp = ctx->use_ltp + c;
1396  bd.ltp_lag = ctx->ltp_lag + c;
1397  bd.ltp_gain = ctx->ltp_gain[c];
1398  bd.lpc_cof = ctx->lpc_cof[c];
1399  bd.quant_cof = ctx->quant_cof[c];
1400  bd.raw_samples = ctx->raw_samples[c] + offset;
1401  bd.raw_other = NULL;
1402 
1403  read_block(ctx, &bd);
1404  if (read_channel_data(ctx, ctx->chan_data[c], c))
1405  return -1;
1406  }
1407 
1408  for (c = 0; c < avctx->channels; c++) {
1409  ret = revert_channel_correlation(ctx, &bd, ctx->chan_data,
1410  reverted_channels, offset, c);
1411  if (ret < 0)
1412  return ret;
1413  }
1414  for (c = 0; c < avctx->channels; c++) {
1415  bd.const_block = ctx->const_block + c;
1416  bd.shift_lsbs = ctx->shift_lsbs + c;
1417  bd.opt_order = ctx->opt_order + c;
1418  bd.store_prev_samples = ctx->store_prev_samples + c;
1419  bd.use_ltp = ctx->use_ltp + c;
1420  bd.ltp_lag = ctx->ltp_lag + c;
1421  bd.ltp_gain = ctx->ltp_gain[c];
1422  bd.lpc_cof = ctx->lpc_cof[c];
1423  bd.quant_cof = ctx->quant_cof[c];
1424  bd.raw_samples = ctx->raw_samples[c] + offset;
1425  decode_block(ctx, &bd);
1426  }
1427 
1428  memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1429  offset += div_blocks[b];
1430  bd.ra_block = 0;
1431  }
1432 
1433  // store carryover raw samples
1434  for (c = 0; c < avctx->channels; c++)
1435  memmove(ctx->raw_samples[c] - sconf->max_order,
1436  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1437  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1438  }
1439 
1440  // TODO: read_diff_float_data
1441 
1442  return 0;
1443 }
1444 
1445 
1448 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1449  AVPacket *avpkt)
1450 {
1451  ALSDecContext *ctx = avctx->priv_data;
1452  ALSSpecificConfig *sconf = &ctx->sconf;
1453  const uint8_t *buffer = avpkt->data;
1454  int buffer_size = avpkt->size;
1455  int invalid_frame, ret;
1456  unsigned int c, sample, ra_frame, bytes_read, shift;
1457 
1458  init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1459 
1460  // In the case that the distance between random access frames is set to zero
1461  // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1462  // For the first frame, if prediction is used, all samples used from the
1463  // previous frame are assumed to be zero.
1464  ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1465 
1466  // the last frame to decode might have a different length
1467  if (sconf->samples != 0xFFFFFFFF)
1468  ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1469  sconf->frame_length);
1470  else
1471  ctx->cur_frame_length = sconf->frame_length;
1472 
1473  // decode the frame data
1474  if ((invalid_frame = read_frame_data(ctx, ra_frame) < 0))
1475  av_log(ctx->avctx, AV_LOG_WARNING,
1476  "Reading frame data failed. Skipping RA unit.\n");
1477 
1478  ctx->frame_id++;
1479 
1480  /* get output buffer */
1481  ctx->frame.nb_samples = ctx->cur_frame_length;
1482  if ((ret = avctx->get_buffer(avctx, &ctx->frame)) < 0) {
1483  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
1484  return ret;
1485  }
1486 
1487  // transform decoded frame into output format
1488  #define INTERLEAVE_OUTPUT(bps) \
1489  { \
1490  int##bps##_t *dest = (int##bps##_t*)ctx->frame.data[0]; \
1491  shift = bps - ctx->avctx->bits_per_raw_sample; \
1492  for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1493  for (c = 0; c < avctx->channels; c++) \
1494  *dest++ = ctx->raw_samples[c][sample] << shift; \
1495  }
1496 
1497  if (ctx->avctx->bits_per_raw_sample <= 16) {
1498  INTERLEAVE_OUTPUT(16)
1499  } else {
1500  INTERLEAVE_OUTPUT(32)
1501  }
1502 
1503  // update CRC
1504  if (sconf->crc_enabled && (avctx->err_recognition & AV_EF_CRCCHECK)) {
1505  int swap = HAVE_BIGENDIAN != sconf->msb_first;
1506 
1507  if (ctx->avctx->bits_per_raw_sample == 24) {
1508  int32_t *src = (int32_t *)ctx->frame.data[0];
1509 
1510  for (sample = 0;
1511  sample < ctx->cur_frame_length * avctx->channels;
1512  sample++) {
1513  int32_t v;
1514 
1515  if (swap)
1516  v = av_bswap32(src[sample]);
1517  else
1518  v = src[sample];
1519  if (!HAVE_BIGENDIAN)
1520  v >>= 8;
1521 
1522  ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1523  }
1524  } else {
1525  uint8_t *crc_source;
1526 
1527  if (swap) {
1528  if (ctx->avctx->bits_per_raw_sample <= 16) {
1529  int16_t *src = (int16_t*) ctx->frame.data[0];
1530  int16_t *dest = (int16_t*) ctx->crc_buffer;
1531  for (sample = 0;
1532  sample < ctx->cur_frame_length * avctx->channels;
1533  sample++)
1534  *dest++ = av_bswap16(src[sample]);
1535  } else {
1536  ctx->dsp.bswap_buf((uint32_t*)ctx->crc_buffer,
1537  (uint32_t *)ctx->frame.data[0],
1538  ctx->cur_frame_length * avctx->channels);
1539  }
1540  crc_source = ctx->crc_buffer;
1541  } else {
1542  crc_source = ctx->frame.data[0];
1543  }
1544 
1545  ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1546  ctx->cur_frame_length * avctx->channels *
1548  }
1549 
1550 
1551  // check CRC sums if this is the last frame
1552  if (ctx->cur_frame_length != sconf->frame_length &&
1553  ctx->crc_org != ctx->crc) {
1554  av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1555  }
1556  }
1557 
1558  *got_frame_ptr = 1;
1559  *(AVFrame *)data = ctx->frame;
1560 
1561 
1562  bytes_read = invalid_frame ? buffer_size :
1563  (get_bits_count(&ctx->gb) + 7) >> 3;
1564 
1565  return bytes_read;
1566 }
1567 
1568 
1572 {
1573  ALSDecContext *ctx = avctx->priv_data;
1574 
1575  av_freep(&ctx->sconf.chan_pos);
1576 
1577  ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1578 
1579  av_freep(&ctx->const_block);
1580  av_freep(&ctx->shift_lsbs);
1581  av_freep(&ctx->opt_order);
1583  av_freep(&ctx->use_ltp);
1584  av_freep(&ctx->ltp_lag);
1585  av_freep(&ctx->ltp_gain);
1586  av_freep(&ctx->ltp_gain_buffer);
1587  av_freep(&ctx->quant_cof);
1588  av_freep(&ctx->lpc_cof);
1589  av_freep(&ctx->quant_cof_buffer);
1590  av_freep(&ctx->lpc_cof_buffer);
1592  av_freep(&ctx->prev_raw_samples);
1593  av_freep(&ctx->raw_samples);
1594  av_freep(&ctx->raw_buffer);
1595  av_freep(&ctx->chan_data);
1596  av_freep(&ctx->chan_data_buffer);
1597  av_freep(&ctx->reverted_channels);
1598  av_freep(&ctx->crc_buffer);
1599 
1600  return 0;
1601 }
1602 
1603 
1607 {
1608  unsigned int c;
1609  unsigned int channel_size;
1610  int num_buffers, ret;
1611  ALSDecContext *ctx = avctx->priv_data;
1612  ALSSpecificConfig *sconf = &ctx->sconf;
1613  ctx->avctx = avctx;
1614 
1615  if (!avctx->extradata) {
1616  av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1617  return AVERROR_INVALIDDATA;
1618  }
1619 
1620  if ((ret = read_specific_config(ctx)) < 0) {
1621  av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1622  goto fail;
1623  }
1624 
1625  if ((ret = check_specific_config(ctx)) < 0) {
1626  goto fail;
1627  }
1628 
1629  if (sconf->bgmc) {
1630  ret = ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1631  if (ret < 0)
1632  goto fail;
1633  }
1634 
1635  if (sconf->floating) {
1636  avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1637  avctx->bits_per_raw_sample = 32;
1638  } else {
1639  avctx->sample_fmt = sconf->resolution > 1
1641  avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1642  }
1643 
1644  // set maximum Rice parameter for progressive decoding based on resolution
1645  // This is not specified in 14496-3 but actually done by the reference
1646  // codec RM22 revision 2.
1647  ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1648 
1649  // set lag value for long-term prediction
1650  ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1651  (avctx->sample_rate >= 192000);
1652 
1653  // allocate quantized parcor coefficient buffer
1654  num_buffers = sconf->mc_coding ? avctx->channels : 1;
1655 
1656  ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1657  ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1658  ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1659  num_buffers * sconf->max_order);
1660  ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1661  num_buffers * sconf->max_order);
1662  ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1663  sconf->max_order);
1664 
1665  if (!ctx->quant_cof || !ctx->lpc_cof ||
1666  !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1667  !ctx->lpc_cof_reversed_buffer) {
1668  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1669  ret = AVERROR(ENOMEM);
1670  goto fail;
1671  }
1672 
1673  // assign quantized parcor coefficient buffers
1674  for (c = 0; c < num_buffers; c++) {
1675  ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1676  ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1677  }
1678 
1679  // allocate and assign lag and gain data buffer for ltp mode
1680  ctx->const_block = av_malloc (sizeof(*ctx->const_block) * num_buffers);
1681  ctx->shift_lsbs = av_malloc (sizeof(*ctx->shift_lsbs) * num_buffers);
1682  ctx->opt_order = av_malloc (sizeof(*ctx->opt_order) * num_buffers);
1683  ctx->store_prev_samples = av_malloc(sizeof(*ctx->store_prev_samples) * num_buffers);
1684  ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1685  ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1686  ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1687  ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1688  num_buffers * 5);
1689 
1690  if (!ctx->const_block || !ctx->shift_lsbs ||
1691  !ctx->opt_order || !ctx->store_prev_samples ||
1692  !ctx->use_ltp || !ctx->ltp_lag ||
1693  !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1694  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1695  ret = AVERROR(ENOMEM);
1696  goto fail;
1697  }
1698 
1699  for (c = 0; c < num_buffers; c++)
1700  ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1701 
1702  // allocate and assign channel data buffer for mcc mode
1703  if (sconf->mc_coding) {
1704  ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1705  num_buffers * num_buffers);
1706  ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) *
1707  num_buffers);
1708  ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1709  num_buffers);
1710 
1711  if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1712  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1713  ret = AVERROR(ENOMEM);
1714  goto fail;
1715  }
1716 
1717  for (c = 0; c < num_buffers; c++)
1718  ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
1719  } else {
1720  ctx->chan_data = NULL;
1721  ctx->chan_data_buffer = NULL;
1722  ctx->reverted_channels = NULL;
1723  }
1724 
1725  avctx->frame_size = sconf->frame_length;
1726  channel_size = sconf->frame_length + sconf->max_order;
1727 
1728  ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1729  ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1730  ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1731 
1732  // allocate previous raw sample buffer
1733  if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1734  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1735  ret = AVERROR(ENOMEM);
1736  goto fail;
1737  }
1738 
1739  // assign raw samples buffers
1740  ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1741  for (c = 1; c < avctx->channels; c++)
1742  ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1743 
1744  // allocate crc buffer
1745  if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
1746  (avctx->err_recognition & AV_EF_CRCCHECK)) {
1747  ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) *
1748  ctx->cur_frame_length *
1749  avctx->channels *
1751  if (!ctx->crc_buffer) {
1752  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1753  ret = AVERROR(ENOMEM);
1754  goto fail;
1755  }
1756  }
1757 
1758  dsputil_init(&ctx->dsp, avctx);
1759 
1761  avctx->coded_frame = &ctx->frame;
1762 
1763  return 0;
1764 
1765 fail:
1766  decode_end(avctx);
1767  return ret;
1768 }
1769 
1770 
1773 static av_cold void flush(AVCodecContext *avctx)
1774 {
1775  ALSDecContext *ctx = avctx->priv_data;
1776 
1777  ctx->frame_id = 0;
1778 }
1779 
1780 
1782  .name = "als",
1783  .type = AVMEDIA_TYPE_AUDIO,
1784  .id = CODEC_ID_MP4ALS,
1785  .priv_data_size = sizeof(ALSDecContext),
1786  .init = decode_init,
1787  .close = decode_end,
1788  .decode = decode_frame,
1789  .flush = flush,
1790  .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
1791  .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),
1792 };
1793