Libav
alsdec.c
Go to the documentation of this file.
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 
28 #include "avcodec.h"
29 #include "get_bits.h"
30 #include "unary.h"
31 #include "mpeg4audio.h"
32 #include "bytestream.h"
33 #include "bgmc.h"
34 #include "dsputil.h"
35 #include "internal.h"
36 #include "libavutil/samplefmt.h"
37 #include "libavutil/crc.h"
38 
39 #include <stdint.h>
40 
45 static const int8_t parcor_rice_table[3][20][2] = {
46  { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
47  { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
48  { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
49  { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
50  { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
51  { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
52  {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
53  { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
54  { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
55  { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
56  {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
57  { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
58 };
59 
60 
66 static const int16_t parcor_scaled_values[] = {
67  -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
68  -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
69  -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
70  -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
71  -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
72  -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
73  -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
74  -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
75  -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
76  -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
77  -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
78  -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
79  -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
80  -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
81  -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
82  -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
83  -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
84  -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
85  -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
86  -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
87  -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
88  -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
89  -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
90  46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
91  143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
92  244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
93  349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
94  458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
95  571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
96  688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
97  810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
98  935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
99 };
100 
101 
105 static const uint8_t ltp_gain_values [4][4] = {
106  { 0, 8, 16, 24},
107  {32, 40, 48, 56},
108  {64, 70, 76, 82},
109  {88, 92, 96, 100}
110 };
111 
112 
116 static const int16_t mcc_weightings[] = {
117  204, 192, 179, 166, 153, 140, 128, 115,
118  102, 89, 76, 64, 51, 38, 25, 12,
119  0, -12, -25, -38, -51, -64, -76, -89,
120  -102, -115, -128, -140, -153, -166, -179, -192
121 };
122 
123 
126 static const uint8_t tail_code[16][6] = {
127  { 74, 44, 25, 13, 7, 3},
128  { 68, 42, 24, 13, 7, 3},
129  { 58, 39, 23, 13, 7, 3},
130  {126, 70, 37, 19, 10, 5},
131  {132, 70, 37, 20, 10, 5},
132  {124, 70, 38, 20, 10, 5},
133  {120, 69, 37, 20, 11, 5},
134  {116, 67, 37, 20, 11, 5},
135  {108, 66, 36, 20, 10, 5},
136  {102, 62, 36, 20, 10, 5},
137  { 88, 58, 34, 19, 10, 5},
138  {162, 89, 49, 25, 13, 7},
139  {156, 87, 49, 26, 14, 7},
140  {150, 86, 47, 26, 14, 7},
141  {142, 84, 47, 26, 14, 7},
142  {131, 79, 46, 26, 14, 7}
143 };
144 
145 
146 enum RA_Flag {
150 };
151 
152 
153 typedef struct {
154  uint32_t samples;
156  int floating;
157  int msb_first;
160  enum RA_Flag ra_flag;
164  int max_order;
166  int bgmc;
167  int sb_part;
169  int mc_coding;
171  int chan_sort;
172  int rlslms;
174  int *chan_pos;
177 
178 
179 typedef struct {
185  int weighting[6];
187 
188 
189 typedef struct {
194  const AVCRC *crc_table;
195  uint32_t crc_org;
196  uint32_t crc;
197  unsigned int cur_frame_length;
198  unsigned int frame_id;
199  unsigned int js_switch;
200  unsigned int num_blocks;
201  unsigned int s_max;
205  int *const_block;
206  unsigned int *shift_lsbs;
207  unsigned int *opt_order;
209  int *use_ltp;
210  int *ltp_lag;
211  int **ltp_gain;
225 } ALSDecContext;
226 
227 
228 typedef struct {
229  unsigned int block_length;
230  unsigned int ra_block;
231  int *const_block;
232  int js_blocks;
233  unsigned int *shift_lsbs;
234  unsigned int *opt_order;
236  int *use_ltp;
237  int *ltp_lag;
238  int *ltp_gain;
244 } ALSBlockData;
245 
246 
248 {
249 #ifdef DEBUG
250  AVCodecContext *avctx = ctx->avctx;
251  ALSSpecificConfig *sconf = &ctx->sconf;
252 
253  av_dlog(avctx, "resolution = %i\n", sconf->resolution);
254  av_dlog(avctx, "floating = %i\n", sconf->floating);
255  av_dlog(avctx, "frame_length = %i\n", sconf->frame_length);
256  av_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance);
257  av_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag);
258  av_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order);
259  av_dlog(avctx, "coef_table = %i\n", sconf->coef_table);
260  av_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
261  av_dlog(avctx, "max_order = %i\n", sconf->max_order);
262  av_dlog(avctx, "block_switching = %i\n", sconf->block_switching);
263  av_dlog(avctx, "bgmc = %i\n", sconf->bgmc);
264  av_dlog(avctx, "sb_part = %i\n", sconf->sb_part);
265  av_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
266  av_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding);
267  av_dlog(avctx, "chan_config = %i\n", sconf->chan_config);
268  av_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort);
269  av_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms);
270  av_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
271 #endif
272 }
273 
274 
278 {
279  GetBitContext gb;
280  uint64_t ht_size;
281  int i, config_offset;
282  MPEG4AudioConfig m4ac;
283  ALSSpecificConfig *sconf = &ctx->sconf;
284  AVCodecContext *avctx = ctx->avctx;
285  uint32_t als_id, header_size, trailer_size;
286 
287  init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
288 
289  config_offset = avpriv_mpeg4audio_get_config(&m4ac, avctx->extradata,
290  avctx->extradata_size * 8, 1);
291 
292  if (config_offset < 0)
293  return AVERROR_INVALIDDATA;
294 
295  skip_bits_long(&gb, config_offset);
296 
297  if (get_bits_left(&gb) < (30 << 3))
298  return AVERROR_INVALIDDATA;
299 
300  // read the fixed items
301  als_id = get_bits_long(&gb, 32);
302  avctx->sample_rate = m4ac.sample_rate;
303  skip_bits_long(&gb, 32); // sample rate already known
304  sconf->samples = get_bits_long(&gb, 32);
305  avctx->channels = m4ac.channels;
306  skip_bits(&gb, 16); // number of channels already knwon
307  skip_bits(&gb, 3); // skip file_type
308  sconf->resolution = get_bits(&gb, 3);
309  sconf->floating = get_bits1(&gb);
310  sconf->msb_first = get_bits1(&gb);
311  sconf->frame_length = get_bits(&gb, 16) + 1;
312  sconf->ra_distance = get_bits(&gb, 8);
313  sconf->ra_flag = get_bits(&gb, 2);
314  sconf->adapt_order = get_bits1(&gb);
315  sconf->coef_table = get_bits(&gb, 2);
316  sconf->long_term_prediction = get_bits1(&gb);
317  sconf->max_order = get_bits(&gb, 10);
318  sconf->block_switching = get_bits(&gb, 2);
319  sconf->bgmc = get_bits1(&gb);
320  sconf->sb_part = get_bits1(&gb);
321  sconf->joint_stereo = get_bits1(&gb);
322  sconf->mc_coding = get_bits1(&gb);
323  sconf->chan_config = get_bits1(&gb);
324  sconf->chan_sort = get_bits1(&gb);
325  sconf->crc_enabled = get_bits1(&gb);
326  sconf->rlslms = get_bits1(&gb);
327  skip_bits(&gb, 5); // skip 5 reserved bits
328  skip_bits1(&gb); // skip aux_data_enabled
329 
330 
331  // check for ALSSpecificConfig struct
332  if (als_id != MKBETAG('A','L','S','\0'))
333  return AVERROR_INVALIDDATA;
334 
335  ctx->cur_frame_length = sconf->frame_length;
336 
337  // read channel config
338  if (sconf->chan_config)
339  sconf->chan_config_info = get_bits(&gb, 16);
340  // TODO: use this to set avctx->channel_layout
341 
342 
343  // read channel sorting
344  if (sconf->chan_sort && avctx->channels > 1) {
345  int chan_pos_bits = av_ceil_log2(avctx->channels);
346  int bits_needed = avctx->channels * chan_pos_bits + 7;
347  if (get_bits_left(&gb) < bits_needed)
348  return AVERROR_INVALIDDATA;
349 
350  if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
351  return AVERROR(ENOMEM);
352 
353  for (i = 0; i < avctx->channels; i++)
354  sconf->chan_pos[i] = get_bits(&gb, chan_pos_bits);
355 
356  align_get_bits(&gb);
357  // TODO: use this to actually do channel sorting
358  } else {
359  sconf->chan_sort = 0;
360  }
361 
362 
363  // read fixed header and trailer sizes,
364  // if size = 0xFFFFFFFF then there is no data field!
365  if (get_bits_left(&gb) < 64)
366  return AVERROR_INVALIDDATA;
367 
368  header_size = get_bits_long(&gb, 32);
369  trailer_size = get_bits_long(&gb, 32);
370  if (header_size == 0xFFFFFFFF)
371  header_size = 0;
372  if (trailer_size == 0xFFFFFFFF)
373  trailer_size = 0;
374 
375  ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
376 
377 
378  // skip the header and trailer data
379  if (get_bits_left(&gb) < ht_size)
380  return AVERROR_INVALIDDATA;
381 
382  if (ht_size > INT32_MAX)
383  return AVERROR_PATCHWELCOME;
384 
385  skip_bits_long(&gb, ht_size);
386 
387 
388  // initialize CRC calculation
389  if (sconf->crc_enabled) {
390  if (get_bits_left(&gb) < 32)
391  return AVERROR_INVALIDDATA;
392 
393  if (avctx->err_recognition & AV_EF_CRCCHECK) {
395  ctx->crc = 0xFFFFFFFF;
396  ctx->crc_org = ~get_bits_long(&gb, 32);
397  } else
398  skip_bits_long(&gb, 32);
399  }
400 
401 
402  // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
403 
405 
406  return 0;
407 }
408 
409 
413 {
414  ALSSpecificConfig *sconf = &ctx->sconf;
415  int error = 0;
416 
417  // report unsupported feature and set error value
418  #define MISSING_ERR(cond, str, errval) \
419  { \
420  if (cond) { \
421  avpriv_report_missing_feature(ctx->avctx, \
422  str); \
423  error = errval; \
424  } \
425  }
426 
427  MISSING_ERR(sconf->floating, "Floating point decoding", AVERROR_PATCHWELCOME);
428  MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME);
429  MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
430 
431  return error;
432 }
433 
434 
438 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
439  unsigned int div, unsigned int **div_blocks,
440  unsigned int *num_blocks)
441 {
442  if (n < 31 && ((bs_info << n) & 0x40000000)) {
443  // if the level is valid and the investigated bit n is set
444  // then recursively check both children at bits (2n+1) and (2n+2)
445  n *= 2;
446  div += 1;
447  parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
448  parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
449  } else {
450  // else the bit is not set or the last level has been reached
451  // (bit implicitly not set)
452  **div_blocks = div;
453  (*div_blocks)++;
454  (*num_blocks)++;
455  }
456 }
457 
458 
461 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
462 {
463  int max = get_bits_left(gb) - k;
464  int q = get_unary(gb, 0, max);
465  int r = k ? get_bits1(gb) : !(q & 1);
466 
467  if (k > 1) {
468  q <<= (k - 1);
469  q += get_bits_long(gb, k - 1);
470  } else if (!k) {
471  q >>= 1;
472  }
473  return r ? q : ~q;
474 }
475 
476 
479 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
480 {
481  int i, j;
482 
483  for (i = 0, j = k - 1; i < j; i++, j--) {
484  int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
485  cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
486  cof[i] += tmp1;
487  }
488  if (i == j)
489  cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
490 
491  cof[k] = par[k];
492 }
493 
494 
499 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
500  uint32_t *bs_info)
501 {
502  ALSSpecificConfig *sconf = &ctx->sconf;
503  GetBitContext *gb = &ctx->gb;
504  unsigned int *ptr_div_blocks = div_blocks;
505  unsigned int b;
506 
507  if (sconf->block_switching) {
508  unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
509  *bs_info = get_bits_long(gb, bs_info_len);
510  *bs_info <<= (32 - bs_info_len);
511  }
512 
513  ctx->num_blocks = 0;
514  parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
515 
516  // The last frame may have an overdetermined block structure given in
517  // the bitstream. In that case the defined block structure would need
518  // more samples than available to be consistent.
519  // The block structure is actually used but the block sizes are adapted
520  // to fit the actual number of available samples.
521  // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
522  // This results in the actual block sizes: 2 2 1 0.
523  // This is not specified in 14496-3 but actually done by the reference
524  // codec RM22 revision 2.
525  // This appears to happen in case of an odd number of samples in the last
526  // frame which is actually not allowed by the block length switching part
527  // of 14496-3.
528  // The ALS conformance files feature an odd number of samples in the last
529  // frame.
530 
531  for (b = 0; b < ctx->num_blocks; b++)
532  div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
533 
534  if (ctx->cur_frame_length != ctx->sconf.frame_length) {
535  unsigned int remaining = ctx->cur_frame_length;
536 
537  for (b = 0; b < ctx->num_blocks; b++) {
538  if (remaining <= div_blocks[b]) {
539  div_blocks[b] = remaining;
540  ctx->num_blocks = b + 1;
541  break;
542  }
543 
544  remaining -= div_blocks[b];
545  }
546  }
547 }
548 
549 
553 {
554  ALSSpecificConfig *sconf = &ctx->sconf;
555  AVCodecContext *avctx = ctx->avctx;
556  GetBitContext *gb = &ctx->gb;
557 
558  *bd->raw_samples = 0;
559  *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
560  bd->js_blocks = get_bits1(gb);
561 
562  // skip 5 reserved bits
563  skip_bits(gb, 5);
564 
565  if (*bd->const_block) {
566  unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
567  *bd->raw_samples = get_sbits_long(gb, const_val_bits);
568  }
569 
570  // ensure constant block decoding by reusing this field
571  *bd->const_block = 1;
572 }
573 
574 
578 {
579  int smp = bd->block_length - 1;
580  int32_t val = *bd->raw_samples;
581  int32_t *dst = bd->raw_samples + 1;
582 
583  // write raw samples into buffer
584  for (; smp; smp--)
585  *dst++ = val;
586 }
587 
588 
592 {
593  ALSSpecificConfig *sconf = &ctx->sconf;
594  AVCodecContext *avctx = ctx->avctx;
595  GetBitContext *gb = &ctx->gb;
596  unsigned int k;
597  unsigned int s[8];
598  unsigned int sx[8];
599  unsigned int sub_blocks, log2_sub_blocks, sb_length;
600  unsigned int start = 0;
601  unsigned int opt_order;
602  int sb;
603  int32_t *quant_cof = bd->quant_cof;
604  int32_t *current_res;
605 
606 
607  // ensure variable block decoding by reusing this field
608  *bd->const_block = 0;
609 
610  *bd->opt_order = 1;
611  bd->js_blocks = get_bits1(gb);
612 
613  opt_order = *bd->opt_order;
614 
615  // determine the number of subblocks for entropy decoding
616  if (!sconf->bgmc && !sconf->sb_part) {
617  log2_sub_blocks = 0;
618  } else {
619  if (sconf->bgmc && sconf->sb_part)
620  log2_sub_blocks = get_bits(gb, 2);
621  else
622  log2_sub_blocks = 2 * get_bits1(gb);
623  }
624 
625  sub_blocks = 1 << log2_sub_blocks;
626 
627  // do not continue in case of a damaged stream since
628  // block_length must be evenly divisible by sub_blocks
629  if (bd->block_length & (sub_blocks - 1)) {
630  av_log(avctx, AV_LOG_WARNING,
631  "Block length is not evenly divisible by the number of subblocks.\n");
632  return AVERROR_INVALIDDATA;
633  }
634 
635  sb_length = bd->block_length >> log2_sub_blocks;
636 
637  if (sconf->bgmc) {
638  s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
639  for (k = 1; k < sub_blocks; k++)
640  s[k] = s[k - 1] + decode_rice(gb, 2);
641 
642  for (k = 0; k < sub_blocks; k++) {
643  sx[k] = s[k] & 0x0F;
644  s [k] >>= 4;
645  }
646  } else {
647  s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
648  for (k = 1; k < sub_blocks; k++)
649  s[k] = s[k - 1] + decode_rice(gb, 0);
650  }
651  for (k = 1; k < sub_blocks; k++)
652  if (s[k] > 32) {
653  av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n");
654  return AVERROR_INVALIDDATA;
655  }
656 
657  if (get_bits1(gb))
658  *bd->shift_lsbs = get_bits(gb, 4) + 1;
659 
660  *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
661 
662 
663  if (!sconf->rlslms) {
664  if (sconf->adapt_order && sconf->max_order) {
665  int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
666  2, sconf->max_order + 1));
667  *bd->opt_order = get_bits(gb, opt_order_length);
668  if (*bd->opt_order > sconf->max_order) {
669  *bd->opt_order = sconf->max_order;
670  av_log(avctx, AV_LOG_ERROR, "Predictor order too large!\n");
671  return AVERROR_INVALIDDATA;
672  }
673  } else {
674  *bd->opt_order = sconf->max_order;
675  }
676 
677  opt_order = *bd->opt_order;
678 
679  if (opt_order) {
680  int add_base;
681 
682  if (sconf->coef_table == 3) {
683  add_base = 0x7F;
684 
685  // read coefficient 0
686  quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
687 
688  // read coefficient 1
689  if (opt_order > 1)
690  quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
691 
692  // read coefficients 2 to opt_order
693  for (k = 2; k < opt_order; k++)
694  quant_cof[k] = get_bits(gb, 7);
695  } else {
696  int k_max;
697  add_base = 1;
698 
699  // read coefficient 0 to 19
700  k_max = FFMIN(opt_order, 20);
701  for (k = 0; k < k_max; k++) {
702  int rice_param = parcor_rice_table[sconf->coef_table][k][1];
703  int offset = parcor_rice_table[sconf->coef_table][k][0];
704  quant_cof[k] = decode_rice(gb, rice_param) + offset;
705  if (quant_cof[k] < -64 || quant_cof[k] > 63) {
706  av_log(avctx, AV_LOG_ERROR, "quant_cof %d is out of range\n", quant_cof[k]);
707  return AVERROR_INVALIDDATA;
708  }
709  }
710 
711  // read coefficients 20 to 126
712  k_max = FFMIN(opt_order, 127);
713  for (; k < k_max; k++)
714  quant_cof[k] = decode_rice(gb, 2) + (k & 1);
715 
716  // read coefficients 127 to opt_order
717  for (; k < opt_order; k++)
718  quant_cof[k] = decode_rice(gb, 1);
719 
720  quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
721 
722  if (opt_order > 1)
723  quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
724  }
725 
726  for (k = 2; k < opt_order; k++)
727  quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
728  }
729  }
730 
731  // read LTP gain and lag values
732  if (sconf->long_term_prediction) {
733  *bd->use_ltp = get_bits1(gb);
734 
735  if (*bd->use_ltp) {
736  int r, c;
737 
738  bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
739  bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
740 
741  r = get_unary(gb, 0, 3);
742  c = get_bits(gb, 2);
743  bd->ltp_gain[2] = ltp_gain_values[r][c];
744 
745  bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
746  bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
747 
748  *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
749  *bd->ltp_lag += FFMAX(4, opt_order + 1);
750  }
751  }
752 
753  // read first value and residuals in case of a random access block
754  if (bd->ra_block) {
755  if (opt_order)
756  bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
757  if (opt_order > 1)
758  bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
759  if (opt_order > 2)
760  bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
761 
762  start = FFMIN(opt_order, 3);
763  }
764 
765  // read all residuals
766  if (sconf->bgmc) {
767  int delta[8];
768  unsigned int k [8];
769  unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
770 
771  // read most significant bits
772  unsigned int high;
773  unsigned int low;
774  unsigned int value;
775 
776  ff_bgmc_decode_init(gb, &high, &low, &value);
777 
778  current_res = bd->raw_samples + start;
779 
780  for (sb = 0; sb < sub_blocks; sb++) {
781  unsigned int sb_len = sb_length - (sb ? 0 : start);
782 
783  k [sb] = s[sb] > b ? s[sb] - b : 0;
784  delta[sb] = 5 - s[sb] + k[sb];
785 
786  ff_bgmc_decode(gb, sb_len, current_res,
787  delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
788 
789  current_res += sb_len;
790  }
791 
792  ff_bgmc_decode_end(gb);
793 
794 
795  // read least significant bits and tails
796  current_res = bd->raw_samples + start;
797 
798  for (sb = 0; sb < sub_blocks; sb++, start = 0) {
799  unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
800  unsigned int cur_k = k[sb];
801  unsigned int cur_s = s[sb];
802 
803  for (; start < sb_length; start++) {
804  int32_t res = *current_res;
805 
806  if (res == cur_tail_code) {
807  unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
808  << (5 - delta[sb]);
809 
810  res = decode_rice(gb, cur_s);
811 
812  if (res >= 0) {
813  res += (max_msb ) << cur_k;
814  } else {
815  res -= (max_msb - 1) << cur_k;
816  }
817  } else {
818  if (res > cur_tail_code)
819  res--;
820 
821  if (res & 1)
822  res = -res;
823 
824  res >>= 1;
825 
826  if (cur_k) {
827  res <<= cur_k;
828  res |= get_bits_long(gb, cur_k);
829  }
830  }
831 
832  *current_res++ = res;
833  }
834  }
835  } else {
836  current_res = bd->raw_samples + start;
837 
838  for (sb = 0; sb < sub_blocks; sb++, start = 0)
839  for (; start < sb_length; start++)
840  *current_res++ = decode_rice(gb, s[sb]);
841  }
842 
843  if (!sconf->mc_coding || ctx->js_switch)
844  align_get_bits(gb);
845 
846  return 0;
847 }
848 
849 
853 {
854  ALSSpecificConfig *sconf = &ctx->sconf;
855  unsigned int block_length = bd->block_length;
856  unsigned int smp = 0;
857  unsigned int k;
858  int opt_order = *bd->opt_order;
859  int sb;
860  int64_t y;
861  int32_t *quant_cof = bd->quant_cof;
862  int32_t *lpc_cof = bd->lpc_cof;
863  int32_t *raw_samples = bd->raw_samples;
864  int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
865  int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
866 
867  // reverse long-term prediction
868  if (*bd->use_ltp) {
869  int ltp_smp;
870 
871  for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
872  int center = ltp_smp - *bd->ltp_lag;
873  int begin = FFMAX(0, center - 2);
874  int end = center + 3;
875  int tab = 5 - (end - begin);
876  int base;
877 
878  y = 1 << 6;
879 
880  for (base = begin; base < end; base++, tab++)
881  y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
882 
883  raw_samples[ltp_smp] += y >> 7;
884  }
885  }
886 
887  // reconstruct all samples from residuals
888  if (bd->ra_block) {
889  for (smp = 0; smp < opt_order; smp++) {
890  y = 1 << 19;
891 
892  for (sb = 0; sb < smp; sb++)
893  y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
894 
895  *raw_samples++ -= y >> 20;
896  parcor_to_lpc(smp, quant_cof, lpc_cof);
897  }
898  } else {
899  for (k = 0; k < opt_order; k++)
900  parcor_to_lpc(k, quant_cof, lpc_cof);
901 
902  // store previous samples in case that they have to be altered
903  if (*bd->store_prev_samples)
904  memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
905  sizeof(*bd->prev_raw_samples) * sconf->max_order);
906 
907  // reconstruct difference signal for prediction (joint-stereo)
908  if (bd->js_blocks && bd->raw_other) {
909  int32_t *left, *right;
910 
911  if (bd->raw_other > raw_samples) { // D = R - L
912  left = raw_samples;
913  right = bd->raw_other;
914  } else { // D = R - L
915  left = bd->raw_other;
916  right = raw_samples;
917  }
918 
919  for (sb = -1; sb >= -sconf->max_order; sb--)
920  raw_samples[sb] = right[sb] - left[sb];
921  }
922 
923  // reconstruct shifted signal
924  if (*bd->shift_lsbs)
925  for (sb = -1; sb >= -sconf->max_order; sb--)
926  raw_samples[sb] >>= *bd->shift_lsbs;
927  }
928 
929  // reverse linear prediction coefficients for efficiency
930  lpc_cof = lpc_cof + opt_order;
931 
932  for (sb = 0; sb < opt_order; sb++)
933  lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
934 
935  // reconstruct raw samples
936  raw_samples = bd->raw_samples + smp;
937  lpc_cof = lpc_cof_reversed + opt_order;
938 
939  for (; raw_samples < raw_samples_end; raw_samples++) {
940  y = 1 << 19;
941 
942  for (sb = -opt_order; sb < 0; sb++)
943  y += MUL64(lpc_cof[sb], raw_samples[sb]);
944 
945  *raw_samples -= y >> 20;
946  }
947 
948  raw_samples = bd->raw_samples;
949 
950  // restore previous samples in case that they have been altered
951  if (*bd->store_prev_samples)
952  memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
953  sizeof(*raw_samples) * sconf->max_order);
954 
955  return 0;
956 }
957 
958 
961 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
962 {
963  int ret = 0;
964  GetBitContext *gb = &ctx->gb;
965 
966  *bd->shift_lsbs = 0;
967  // read block type flag and read the samples accordingly
968  if (get_bits1(gb)) {
969  ret = read_var_block_data(ctx, bd);
970  } else {
971  read_const_block_data(ctx, bd);
972  }
973 
974  return ret;
975 }
976 
977 
981 {
982  unsigned int smp;
983  int ret = 0;
984 
985  // read block type flag and read the samples accordingly
986  if (*bd->const_block)
987  decode_const_block_data(ctx, bd);
988  else
989  ret = decode_var_block_data(ctx, bd); // always return 0
990 
991  if (ret < 0)
992  return ret;
993 
994  // TODO: read RLSLMS extension data
995 
996  if (*bd->shift_lsbs)
997  for (smp = 0; smp < bd->block_length; smp++)
998  bd->raw_samples[smp] <<= *bd->shift_lsbs;
999 
1000  return 0;
1001 }
1002 
1003 
1007 {
1008  int ret;
1009 
1010  if ((ret = read_block(ctx, bd)) < 0)
1011  return ret;
1012 
1013  return decode_block(ctx, bd);
1014 }
1015 
1016 
1020 static void zero_remaining(unsigned int b, unsigned int b_max,
1021  const unsigned int *div_blocks, int32_t *buf)
1022 {
1023  unsigned int count = 0;
1024 
1025  for (; b < b_max; b++)
1026  count += div_blocks[b];
1027 
1028  if (count)
1029  memset(buf, 0, sizeof(*buf) * count);
1030 }
1031 
1032 
1035 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1036  unsigned int c, const unsigned int *div_blocks,
1037  unsigned int *js_blocks)
1038 {
1039  int ret;
1040  unsigned int b;
1041  ALSBlockData bd = { 0 };
1042 
1043  bd.ra_block = ra_frame;
1044  bd.const_block = ctx->const_block;
1045  bd.shift_lsbs = ctx->shift_lsbs;
1046  bd.opt_order = ctx->opt_order;
1048  bd.use_ltp = ctx->use_ltp;
1049  bd.ltp_lag = ctx->ltp_lag;
1050  bd.ltp_gain = ctx->ltp_gain[0];
1051  bd.quant_cof = ctx->quant_cof[0];
1052  bd.lpc_cof = ctx->lpc_cof[0];
1054  bd.raw_samples = ctx->raw_samples[c];
1055 
1056 
1057  for (b = 0; b < ctx->num_blocks; b++) {
1058  bd.block_length = div_blocks[b];
1059 
1060  if ((ret = read_decode_block(ctx, &bd)) < 0) {
1061  // damaged block, write zero for the rest of the frame
1062  zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1063  return ret;
1064  }
1065  bd.raw_samples += div_blocks[b];
1066  bd.ra_block = 0;
1067  }
1068 
1069  return 0;
1070 }
1071 
1072 
1075 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1076  unsigned int c, const unsigned int *div_blocks,
1077  unsigned int *js_blocks)
1078 {
1079  ALSSpecificConfig *sconf = &ctx->sconf;
1080  unsigned int offset = 0;
1081  unsigned int b;
1082  int ret;
1083  ALSBlockData bd[2] = { { 0 } };
1084 
1085  bd[0].ra_block = ra_frame;
1086  bd[0].const_block = ctx->const_block;
1087  bd[0].shift_lsbs = ctx->shift_lsbs;
1088  bd[0].opt_order = ctx->opt_order;
1090  bd[0].use_ltp = ctx->use_ltp;
1091  bd[0].ltp_lag = ctx->ltp_lag;
1092  bd[0].ltp_gain = ctx->ltp_gain[0];
1093  bd[0].quant_cof = ctx->quant_cof[0];
1094  bd[0].lpc_cof = ctx->lpc_cof[0];
1095  bd[0].prev_raw_samples = ctx->prev_raw_samples;
1096  bd[0].js_blocks = *js_blocks;
1097 
1098  bd[1].ra_block = ra_frame;
1099  bd[1].const_block = ctx->const_block;
1100  bd[1].shift_lsbs = ctx->shift_lsbs;
1101  bd[1].opt_order = ctx->opt_order;
1103  bd[1].use_ltp = ctx->use_ltp;
1104  bd[1].ltp_lag = ctx->ltp_lag;
1105  bd[1].ltp_gain = ctx->ltp_gain[0];
1106  bd[1].quant_cof = ctx->quant_cof[0];
1107  bd[1].lpc_cof = ctx->lpc_cof[0];
1108  bd[1].prev_raw_samples = ctx->prev_raw_samples;
1109  bd[1].js_blocks = *(js_blocks + 1);
1110 
1111  // decode all blocks
1112  for (b = 0; b < ctx->num_blocks; b++) {
1113  unsigned int s;
1114 
1115  bd[0].block_length = div_blocks[b];
1116  bd[1].block_length = div_blocks[b];
1117 
1118  bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1119  bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1120 
1121  bd[0].raw_other = bd[1].raw_samples;
1122  bd[1].raw_other = bd[0].raw_samples;
1123 
1124  if ((ret = read_decode_block(ctx, &bd[0])) < 0 ||
1125  (ret = read_decode_block(ctx, &bd[1])) < 0)
1126  goto fail;
1127 
1128  // reconstruct joint-stereo blocks
1129  if (bd[0].js_blocks) {
1130  if (bd[1].js_blocks)
1131  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair!\n");
1132 
1133  for (s = 0; s < div_blocks[b]; s++)
1134  bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1135  } else if (bd[1].js_blocks) {
1136  for (s = 0; s < div_blocks[b]; s++)
1137  bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1138  }
1139 
1140  offset += div_blocks[b];
1141  bd[0].ra_block = 0;
1142  bd[1].ra_block = 0;
1143  }
1144 
1145  // store carryover raw samples,
1146  // the others channel raw samples are stored by the calling function.
1147  memmove(ctx->raw_samples[c] - sconf->max_order,
1148  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1149  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1150 
1151  return 0;
1152 fail:
1153  // damaged block, write zero for the rest of the frame
1154  zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1155  zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1156  return ret;
1157 }
1158 
1159 static inline int als_weighting(GetBitContext *gb, int k, int off)
1160 {
1161  int idx = av_clip(decode_rice(gb, k) + off,
1162  0, FF_ARRAY_ELEMS(mcc_weightings) - 1);
1163  return mcc_weightings[idx];
1164 }
1165 
1168 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1169 {
1170  GetBitContext *gb = &ctx->gb;
1171  ALSChannelData *current = cd;
1172  unsigned int channels = ctx->avctx->channels;
1173  int entries = 0;
1174 
1175  while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1176  current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1177 
1178  if (current->master_channel >= channels) {
1179  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel!\n");
1180  return AVERROR_INVALIDDATA;
1181  }
1182 
1183  if (current->master_channel != c) {
1184  current->time_diff_flag = get_bits1(gb);
1185  current->weighting[0] = als_weighting(gb, 1, 16);
1186  current->weighting[1] = als_weighting(gb, 2, 14);
1187  current->weighting[2] = als_weighting(gb, 1, 16);
1188 
1189  if (current->time_diff_flag) {
1190  current->weighting[3] = als_weighting(gb, 1, 16);
1191  current->weighting[4] = als_weighting(gb, 1, 16);
1192  current->weighting[5] = als_weighting(gb, 1, 16);
1193 
1194  current->time_diff_sign = get_bits1(gb);
1195  current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1196  }
1197  }
1198 
1199  current++;
1200  entries++;
1201  }
1202 
1203  if (entries == channels) {
1204  av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data!\n");
1205  return AVERROR_INVALIDDATA;
1206  }
1207 
1208  align_get_bits(gb);
1209  return 0;
1210 }
1211 
1212 
1216  ALSChannelData **cd, int *reverted,
1217  unsigned int offset, int c)
1218 {
1219  ALSChannelData *ch = cd[c];
1220  unsigned int dep = 0;
1221  unsigned int channels = ctx->avctx->channels;
1222  unsigned int channel_size = ctx->sconf.frame_length + ctx->sconf.max_order;
1223 
1224  if (reverted[c])
1225  return 0;
1226 
1227  reverted[c] = 1;
1228 
1229  while (dep < channels && !ch[dep].stop_flag) {
1230  revert_channel_correlation(ctx, bd, cd, reverted, offset,
1231  ch[dep].master_channel);
1232 
1233  dep++;
1234  }
1235 
1236  if (dep == channels) {
1237  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation!\n");
1238  return AVERROR_INVALIDDATA;
1239  }
1240 
1241  bd->const_block = ctx->const_block + c;
1242  bd->shift_lsbs = ctx->shift_lsbs + c;
1243  bd->opt_order = ctx->opt_order + c;
1244  bd->store_prev_samples = ctx->store_prev_samples + c;
1245  bd->use_ltp = ctx->use_ltp + c;
1246  bd->ltp_lag = ctx->ltp_lag + c;
1247  bd->ltp_gain = ctx->ltp_gain[c];
1248  bd->lpc_cof = ctx->lpc_cof[c];
1249  bd->quant_cof = ctx->quant_cof[c];
1250  bd->raw_samples = ctx->raw_samples[c] + offset;
1251 
1252  dep = 0;
1253  while (!ch[dep].stop_flag) {
1254  ptrdiff_t smp;
1255  ptrdiff_t begin = 1;
1256  ptrdiff_t end = bd->block_length - 1;
1257  int64_t y;
1258  int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1259 
1260  if (ch[dep].time_diff_flag) {
1261  int t = ch[dep].time_diff_index;
1262 
1263  if (ch[dep].time_diff_sign) {
1264  t = -t;
1265  begin -= t;
1266  } else {
1267  end -= t;
1268  }
1269 
1270  if (FFMIN(begin - 1, begin - 1 + t) < ctx->raw_buffer - master ||
1271  FFMAX(end + 1, end + 1 + t) > ctx->raw_buffer + channels * channel_size - master) {
1272  av_log(ctx->avctx, AV_LOG_ERROR,
1273  "sample pointer range [%p, %p] not contained in raw_buffer [%p, %p].\n",
1274  master + FFMIN(begin - 1, begin - 1 + t), master + FFMAX(end + 1, end + 1 + t),
1275  ctx->raw_buffer, ctx->raw_buffer + channels * channel_size);
1276  return AVERROR_INVALIDDATA;
1277  }
1278 
1279  for (smp = begin; smp < end; smp++) {
1280  y = (1 << 6) +
1281  MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1282  MUL64(ch[dep].weighting[1], master[smp ]) +
1283  MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1284  MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1285  MUL64(ch[dep].weighting[4], master[smp + t]) +
1286  MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1287 
1288  bd->raw_samples[smp] += y >> 7;
1289  }
1290  } else {
1291 
1292  if (begin - 1 < ctx->raw_buffer - master ||
1293  end + 1 > ctx->raw_buffer + channels * channel_size - master) {
1294  av_log(ctx->avctx, AV_LOG_ERROR,
1295  "sample pointer range [%p, %p] not contained in raw_buffer [%p, %p].\n",
1296  master + begin - 1, master + end + 1,
1297  ctx->raw_buffer, ctx->raw_buffer + channels * channel_size);
1298  return AVERROR_INVALIDDATA;
1299  }
1300 
1301  for (smp = begin; smp < end; smp++) {
1302  y = (1 << 6) +
1303  MUL64(ch[dep].weighting[0], master[smp - 1]) +
1304  MUL64(ch[dep].weighting[1], master[smp ]) +
1305  MUL64(ch[dep].weighting[2], master[smp + 1]);
1306 
1307  bd->raw_samples[smp] += y >> 7;
1308  }
1309  }
1310 
1311  dep++;
1312  }
1313 
1314  return 0;
1315 }
1316 
1317 
1320 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1321 {
1322  ALSSpecificConfig *sconf = &ctx->sconf;
1323  AVCodecContext *avctx = ctx->avctx;
1324  GetBitContext *gb = &ctx->gb;
1325  unsigned int div_blocks[32];
1326  unsigned int c;
1327  unsigned int js_blocks[2];
1328  uint32_t bs_info = 0;
1329  int ret;
1330 
1331  // skip the size of the ra unit if present in the frame
1332  if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1333  skip_bits_long(gb, 32);
1334 
1335  if (sconf->mc_coding && sconf->joint_stereo) {
1336  ctx->js_switch = get_bits1(gb);
1337  align_get_bits(gb);
1338  }
1339 
1340  if (!sconf->mc_coding || ctx->js_switch) {
1341  int independent_bs = !sconf->joint_stereo;
1342 
1343  for (c = 0; c < avctx->channels; c++) {
1344  js_blocks[0] = 0;
1345  js_blocks[1] = 0;
1346 
1347  get_block_sizes(ctx, div_blocks, &bs_info);
1348 
1349  // if joint_stereo and block_switching is set, independent decoding
1350  // is signaled via the first bit of bs_info
1351  if (sconf->joint_stereo && sconf->block_switching)
1352  if (bs_info >> 31)
1353  independent_bs = 2;
1354 
1355  // if this is the last channel, it has to be decoded independently
1356  if (c == avctx->channels - 1)
1357  independent_bs = 1;
1358 
1359  if (independent_bs) {
1360  ret = decode_blocks_ind(ctx, ra_frame, c,
1361  div_blocks, js_blocks);
1362  if (ret < 0)
1363  return ret;
1364  independent_bs--;
1365  } else {
1366  ret = decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks);
1367  if (ret < 0)
1368  return ret;
1369 
1370  c++;
1371  }
1372 
1373  // store carryover raw samples
1374  memmove(ctx->raw_samples[c] - sconf->max_order,
1375  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1376  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1377  }
1378  } else { // multi-channel coding
1379  ALSBlockData bd = { 0 };
1380  int b, ret;
1381  int *reverted_channels = ctx->reverted_channels;
1382  unsigned int offset = 0;
1383 
1384  for (c = 0; c < avctx->channels; c++)
1385  if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1386  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data!\n");
1387  return AVERROR_INVALIDDATA;
1388  }
1389 
1390  memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1391 
1392  bd.ra_block = ra_frame;
1394 
1395  get_block_sizes(ctx, div_blocks, &bs_info);
1396 
1397  for (b = 0; b < ctx->num_blocks; b++) {
1398  bd.block_length = div_blocks[b];
1399  if (bd.block_length <= 0) {
1400  av_log(ctx->avctx, AV_LOG_WARNING,
1401  "Invalid block length %d in channel data!\n", bd.block_length);
1402  continue;
1403  }
1404 
1405  for (c = 0; c < avctx->channels; c++) {
1406  bd.const_block = ctx->const_block + c;
1407  bd.shift_lsbs = ctx->shift_lsbs + c;
1408  bd.opt_order = ctx->opt_order + c;
1409  bd.store_prev_samples = ctx->store_prev_samples + c;
1410  bd.use_ltp = ctx->use_ltp + c;
1411  bd.ltp_lag = ctx->ltp_lag + c;
1412  bd.ltp_gain = ctx->ltp_gain[c];
1413  bd.lpc_cof = ctx->lpc_cof[c];
1414  bd.quant_cof = ctx->quant_cof[c];
1415  bd.raw_samples = ctx->raw_samples[c] + offset;
1416  bd.raw_other = NULL;
1417 
1418  if ((ret = read_block(ctx, &bd)) < 0)
1419  return ret;
1420  if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0)
1421  return ret;
1422  }
1423 
1424  for (c = 0; c < avctx->channels; c++) {
1425  ret = revert_channel_correlation(ctx, &bd, ctx->chan_data,
1426  reverted_channels, offset, c);
1427  if (ret < 0)
1428  return ret;
1429  }
1430  for (c = 0; c < avctx->channels; c++) {
1431  bd.const_block = ctx->const_block + c;
1432  bd.shift_lsbs = ctx->shift_lsbs + c;
1433  bd.opt_order = ctx->opt_order + c;
1434  bd.store_prev_samples = ctx->store_prev_samples + c;
1435  bd.use_ltp = ctx->use_ltp + c;
1436  bd.ltp_lag = ctx->ltp_lag + c;
1437  bd.ltp_gain = ctx->ltp_gain[c];
1438  bd.lpc_cof = ctx->lpc_cof[c];
1439  bd.quant_cof = ctx->quant_cof[c];
1440  bd.raw_samples = ctx->raw_samples[c] + offset;
1441  if ((ret = decode_block(ctx, &bd)) < 0)
1442  return ret;
1443  }
1444 
1445  memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1446  offset += div_blocks[b];
1447  bd.ra_block = 0;
1448  }
1449 
1450  // store carryover raw samples
1451  for (c = 0; c < avctx->channels; c++)
1452  memmove(ctx->raw_samples[c] - sconf->max_order,
1453  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1454  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1455  }
1456 
1457  // TODO: read_diff_float_data
1458 
1459  return 0;
1460 }
1461 
1462 
1465 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1466  AVPacket *avpkt)
1467 {
1468  ALSDecContext *ctx = avctx->priv_data;
1469  AVFrame *frame = data;
1470  ALSSpecificConfig *sconf = &ctx->sconf;
1471  const uint8_t *buffer = avpkt->data;
1472  int buffer_size = avpkt->size;
1473  int invalid_frame, ret;
1474  unsigned int c, sample, ra_frame, bytes_read, shift;
1475 
1476  init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1477 
1478  // In the case that the distance between random access frames is set to zero
1479  // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1480  // For the first frame, if prediction is used, all samples used from the
1481  // previous frame are assumed to be zero.
1482  ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1483 
1484  // the last frame to decode might have a different length
1485  if (sconf->samples != 0xFFFFFFFF)
1486  ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1487  sconf->frame_length);
1488  else
1489  ctx->cur_frame_length = sconf->frame_length;
1490 
1491  // decode the frame data
1492  if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0)
1493  av_log(ctx->avctx, AV_LOG_WARNING,
1494  "Reading frame data failed. Skipping RA unit.\n");
1495 
1496  ctx->frame_id++;
1497 
1498  /* get output buffer */
1499  frame->nb_samples = ctx->cur_frame_length;
1500  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
1501  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
1502  return ret;
1503  }
1504 
1505  // transform decoded frame into output format
1506  #define INTERLEAVE_OUTPUT(bps) \
1507  { \
1508  int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \
1509  shift = bps - ctx->avctx->bits_per_raw_sample; \
1510  for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1511  for (c = 0; c < avctx->channels; c++) \
1512  *dest++ = ctx->raw_samples[c][sample] << shift; \
1513  }
1514 
1515  if (ctx->avctx->bits_per_raw_sample <= 16) {
1516  INTERLEAVE_OUTPUT(16)
1517  } else {
1518  INTERLEAVE_OUTPUT(32)
1519  }
1520 
1521  // update CRC
1522  if (sconf->crc_enabled && (avctx->err_recognition & AV_EF_CRCCHECK)) {
1523  int swap = HAVE_BIGENDIAN != sconf->msb_first;
1524 
1525  if (ctx->avctx->bits_per_raw_sample == 24) {
1526  int32_t *src = (int32_t *)frame->data[0];
1527 
1528  for (sample = 0;
1529  sample < ctx->cur_frame_length * avctx->channels;
1530  sample++) {
1531  int32_t v;
1532 
1533  if (swap)
1534  v = av_bswap32(src[sample]);
1535  else
1536  v = src[sample];
1537  if (!HAVE_BIGENDIAN)
1538  v >>= 8;
1539 
1540  ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1541  }
1542  } else {
1543  uint8_t *crc_source;
1544 
1545  if (swap) {
1546  if (ctx->avctx->bits_per_raw_sample <= 16) {
1547  int16_t *src = (int16_t*) frame->data[0];
1548  int16_t *dest = (int16_t*) ctx->crc_buffer;
1549  for (sample = 0;
1550  sample < ctx->cur_frame_length * avctx->channels;
1551  sample++)
1552  *dest++ = av_bswap16(src[sample]);
1553  } else {
1554  ctx->dsp.bswap_buf((uint32_t*)ctx->crc_buffer,
1555  (uint32_t *)frame->data[0],
1556  ctx->cur_frame_length * avctx->channels);
1557  }
1558  crc_source = ctx->crc_buffer;
1559  } else {
1560  crc_source = frame->data[0];
1561  }
1562 
1563  ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1564  ctx->cur_frame_length * avctx->channels *
1566  }
1567 
1568 
1569  // check CRC sums if this is the last frame
1570  if (ctx->cur_frame_length != sconf->frame_length &&
1571  ctx->crc_org != ctx->crc) {
1572  av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1573  if (avctx->err_recognition & AV_EF_EXPLODE)
1574  return AVERROR_INVALIDDATA;
1575  }
1576  }
1577 
1578  *got_frame_ptr = 1;
1579 
1580  bytes_read = invalid_frame ? buffer_size :
1581  (get_bits_count(&ctx->gb) + 7) >> 3;
1582 
1583  return bytes_read;
1584 }
1585 
1586 
1590 {
1591  ALSDecContext *ctx = avctx->priv_data;
1592 
1593  av_freep(&ctx->sconf.chan_pos);
1594 
1595  ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1596 
1597  av_freep(&ctx->const_block);
1598  av_freep(&ctx->shift_lsbs);
1599  av_freep(&ctx->opt_order);
1601  av_freep(&ctx->use_ltp);
1602  av_freep(&ctx->ltp_lag);
1603  av_freep(&ctx->ltp_gain);
1604  av_freep(&ctx->ltp_gain_buffer);
1605  av_freep(&ctx->quant_cof);
1606  av_freep(&ctx->lpc_cof);
1607  av_freep(&ctx->quant_cof_buffer);
1608  av_freep(&ctx->lpc_cof_buffer);
1610  av_freep(&ctx->prev_raw_samples);
1611  av_freep(&ctx->raw_samples);
1612  av_freep(&ctx->raw_buffer);
1613  av_freep(&ctx->chan_data);
1614  av_freep(&ctx->chan_data_buffer);
1615  av_freep(&ctx->reverted_channels);
1616  av_freep(&ctx->crc_buffer);
1617 
1618  return 0;
1619 }
1620 
1621 
1625 {
1626  unsigned int c;
1627  unsigned int channel_size;
1628  int num_buffers, ret;
1629  ALSDecContext *ctx = avctx->priv_data;
1630  ALSSpecificConfig *sconf = &ctx->sconf;
1631  ctx->avctx = avctx;
1632 
1633  if (!avctx->extradata) {
1634  av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1635  return AVERROR_INVALIDDATA;
1636  }
1637 
1638  if ((ret = read_specific_config(ctx)) < 0) {
1639  av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1640  goto fail;
1641  }
1642 
1643  if ((ret = check_specific_config(ctx)) < 0) {
1644  goto fail;
1645  }
1646 
1647  if (sconf->bgmc) {
1648  ret = ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1649  if (ret < 0)
1650  goto fail;
1651  }
1652  if (sconf->floating) {
1653  avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1654  avctx->bits_per_raw_sample = 32;
1655  } else {
1656  avctx->sample_fmt = sconf->resolution > 1
1658  avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1659  if (avctx->bits_per_raw_sample > 32) {
1660  av_log(avctx, AV_LOG_ERROR, "Bits per raw sample %d larger than 32.\n",
1661  avctx->bits_per_raw_sample);
1662  ret = AVERROR_INVALIDDATA;
1663  goto fail;
1664  }
1665  }
1666 
1667  // set maximum Rice parameter for progressive decoding based on resolution
1668  // This is not specified in 14496-3 but actually done by the reference
1669  // codec RM22 revision 2.
1670  ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1671 
1672  // set lag value for long-term prediction
1673  ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1674  (avctx->sample_rate >= 192000);
1675 
1676  // allocate quantized parcor coefficient buffer
1677  num_buffers = sconf->mc_coding ? avctx->channels : 1;
1678 
1679  ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1680  ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1681  ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1682  num_buffers * sconf->max_order);
1683  ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1684  num_buffers * sconf->max_order);
1685  ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1686  sconf->max_order);
1687 
1688  if (!ctx->quant_cof || !ctx->lpc_cof ||
1689  !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1690  !ctx->lpc_cof_reversed_buffer) {
1691  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1692  ret = AVERROR(ENOMEM);
1693  goto fail;
1694  }
1695 
1696  // assign quantized parcor coefficient buffers
1697  for (c = 0; c < num_buffers; c++) {
1698  ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1699  ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1700  }
1701 
1702  // allocate and assign lag and gain data buffer for ltp mode
1703  ctx->const_block = av_malloc (sizeof(*ctx->const_block) * num_buffers);
1704  ctx->shift_lsbs = av_malloc (sizeof(*ctx->shift_lsbs) * num_buffers);
1705  ctx->opt_order = av_malloc (sizeof(*ctx->opt_order) * num_buffers);
1706  ctx->store_prev_samples = av_malloc(sizeof(*ctx->store_prev_samples) * num_buffers);
1707  ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1708  ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1709  ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1710  ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1711  num_buffers * 5);
1712 
1713  if (!ctx->const_block || !ctx->shift_lsbs ||
1714  !ctx->opt_order || !ctx->store_prev_samples ||
1715  !ctx->use_ltp || !ctx->ltp_lag ||
1716  !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1717  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1718  ret = AVERROR(ENOMEM);
1719  goto fail;
1720  }
1721 
1722  for (c = 0; c < num_buffers; c++)
1723  ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1724 
1725  // allocate and assign channel data buffer for mcc mode
1726  if (sconf->mc_coding) {
1727  ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1728  num_buffers * num_buffers);
1729  ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) *
1730  num_buffers);
1731  ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1732  num_buffers);
1733 
1734  if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1735  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1736  ret = AVERROR(ENOMEM);
1737  goto fail;
1738  }
1739 
1740  for (c = 0; c < num_buffers; c++)
1741  ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
1742  } else {
1743  ctx->chan_data = NULL;
1744  ctx->chan_data_buffer = NULL;
1745  ctx->reverted_channels = NULL;
1746  }
1747 
1748  channel_size = sconf->frame_length + sconf->max_order;
1749 
1750  ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1751  ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1752  ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1753 
1754  // allocate previous raw sample buffer
1755  if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1756  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1757  ret = AVERROR(ENOMEM);
1758  goto fail;
1759  }
1760 
1761  // assign raw samples buffers
1762  ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1763  for (c = 1; c < avctx->channels; c++)
1764  ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1765 
1766  // allocate crc buffer
1767  if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
1768  (avctx->err_recognition & AV_EF_CRCCHECK)) {
1769  ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) *
1770  ctx->cur_frame_length *
1771  avctx->channels *
1773  if (!ctx->crc_buffer) {
1774  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1775  ret = AVERROR(ENOMEM);
1776  goto fail;
1777  }
1778  }
1779 
1780  ff_dsputil_init(&ctx->dsp, avctx);
1781 
1782  return 0;
1783 
1784 fail:
1785  decode_end(avctx);
1786  return ret;
1787 }
1788 
1789 
1792 static av_cold void flush(AVCodecContext *avctx)
1793 {
1794  ALSDecContext *ctx = avctx->priv_data;
1795 
1796  ctx->frame_id = 0;
1797 }
1798 
1799 
1801  .name = "als",
1802  .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),
1803  .type = AVMEDIA_TYPE_AUDIO,
1804  .id = AV_CODEC_ID_MP4ALS,
1805  .priv_data_size = sizeof(ALSDecContext),
1806  .init = decode_init,
1807  .close = decode_end,
1808  .decode = decode_frame,
1809  .flush = flush,
1810  .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
1811 };