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 "internal.h"
40 #include "libavutil/samplefmt.h"
41 #include "libavutil/crc.h"
42 
43 #include <stdint.h>
44 
49 static const int8_t parcor_rice_table[3][20][2] = {
50  { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
51  { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
52  { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
53  { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
54  { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
55  { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
56  {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
57  { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
58  { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
59  { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
60  {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
61  { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
62 };
63 
64 
70 static const int16_t parcor_scaled_values[] = {
71  -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
72  -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
73  -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
74  -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
75  -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
76  -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
77  -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
78  -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
79  -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
80  -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
81  -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
82  -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
83  -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
84  -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
85  -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
86  -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
87  -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
88  -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
89  -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
90  -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
91  -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
92  -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
93  -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
94  46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
95  143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
96  244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
97  349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
98  458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
99  571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
100  688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
101  810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
102  935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
103 };
104 
105 
109 static const uint8_t ltp_gain_values [4][4] = {
110  { 0, 8, 16, 24},
111  {32, 40, 48, 56},
112  {64, 70, 76, 82},
113  {88, 92, 96, 100}
114 };
115 
116 
120 static const int16_t mcc_weightings[] = {
121  204, 192, 179, 166, 153, 140, 128, 115,
122  102, 89, 76, 64, 51, 38, 25, 12,
123  0, -12, -25, -38, -51, -64, -76, -89,
124  -102, -115, -128, -140, -153, -166, -179, -192
125 };
126 
127 
130 static const uint8_t tail_code[16][6] = {
131  { 74, 44, 25, 13, 7, 3},
132  { 68, 42, 24, 13, 7, 3},
133  { 58, 39, 23, 13, 7, 3},
134  {126, 70, 37, 19, 10, 5},
135  {132, 70, 37, 20, 10, 5},
136  {124, 70, 38, 20, 10, 5},
137  {120, 69, 37, 20, 11, 5},
138  {116, 67, 37, 20, 11, 5},
139  {108, 66, 36, 20, 10, 5},
140  {102, 62, 36, 20, 10, 5},
141  { 88, 58, 34, 19, 10, 5},
142  {162, 89, 49, 25, 13, 7},
143  {156, 87, 49, 26, 14, 7},
144  {150, 86, 47, 26, 14, 7},
145  {142, 84, 47, 26, 14, 7},
146  {131, 79, 46, 26, 14, 7}
147 };
148 
149 
150 enum RA_Flag {
151  RA_FLAG_NONE,
152  RA_FLAG_FRAMES,
153  RA_FLAG_HEADER
154 };
155 
156 
157 typedef struct {
158  uint32_t samples;
159  int resolution;
160  int floating;
161  int msb_first;
162  int frame_length;
163  int ra_distance;
164  enum RA_Flag ra_flag;
165  int adapt_order;
166  int coef_table;
167  int long_term_prediction;
168  int max_order;
169  int block_switching;
170  int bgmc;
171  int sb_part;
172  int joint_stereo;
173  int mc_coding;
174  int chan_config;
175  int chan_sort;
176  int rlslms;
177  int chan_config_info;
178  int *chan_pos;
179  int crc_enabled;
180 } ALSSpecificConfig;
181 
182 
183 typedef struct {
184  int stop_flag;
185  int master_channel;
186  int time_diff_flag;
187  int time_diff_sign;
188  int time_diff_index;
189  int weighting[6];
190 } ALSChannelData;
191 
192 
193 typedef struct {
194  AVCodecContext *avctx;
195  AVFrame frame;
196  ALSSpecificConfig sconf;
197  GetBitContext gb;
198  DSPContext dsp;
199  const AVCRC *crc_table;
200  uint32_t crc_org;
201  uint32_t crc;
202  unsigned int cur_frame_length;
203  unsigned int frame_id;
204  unsigned int js_switch;
205  unsigned int num_blocks;
206  unsigned int s_max;
207  uint8_t *bgmc_lut;
208  int *bgmc_lut_status;
209  int ltp_lag_length;
210  int *const_block;
211  unsigned int *shift_lsbs;
212  unsigned int *opt_order;
213  int *store_prev_samples;
214  int *use_ltp;
215  int *ltp_lag;
216  int **ltp_gain;
217  int *ltp_gain_buffer;
218  int32_t **quant_cof;
219  int32_t *quant_cof_buffer;
220  int32_t **lpc_cof;
221  int32_t *lpc_cof_buffer;
222  int32_t *lpc_cof_reversed_buffer;
223  ALSChannelData **chan_data;
224  ALSChannelData *chan_data_buffer;
225  int *reverted_channels;
226  int32_t *prev_raw_samples;
227  int32_t **raw_samples;
228  int32_t *raw_buffer;
229  uint8_t *crc_buffer;
230 } ALSDecContext;
231 
232 
233 typedef struct {
234  unsigned int block_length;
235  unsigned int ra_block;
236  int *const_block;
237  int js_blocks;
238  unsigned int *shift_lsbs;
239  unsigned int *opt_order;
240  int *store_prev_samples;
241  int *use_ltp;
242  int *ltp_lag;
243  int *ltp_gain;
244  int32_t *quant_cof;
245  int32_t *lpc_cof;
246  int32_t *raw_samples;
247  int32_t *prev_raw_samples;
248  int32_t *raw_other;
249 } ALSBlockData;
250 
251 
252 static av_cold void dprint_specific_config(ALSDecContext *ctx)
253 {
254 #ifdef DEBUG
255  AVCodecContext *avctx = ctx->avctx;
256  ALSSpecificConfig *sconf = &ctx->sconf;
257 
258  av_dlog(avctx, "resolution = %i\n", sconf->resolution);
259  av_dlog(avctx, "floating = %i\n", sconf->floating);
260  av_dlog(avctx, "frame_length = %i\n", sconf->frame_length);
261  av_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance);
262  av_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag);
263  av_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order);
264  av_dlog(avctx, "coef_table = %i\n", sconf->coef_table);
265  av_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
266  av_dlog(avctx, "max_order = %i\n", sconf->max_order);
267  av_dlog(avctx, "block_switching = %i\n", sconf->block_switching);
268  av_dlog(avctx, "bgmc = %i\n", sconf->bgmc);
269  av_dlog(avctx, "sb_part = %i\n", sconf->sb_part);
270  av_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
271  av_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding);
272  av_dlog(avctx, "chan_config = %i\n", sconf->chan_config);
273  av_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort);
274  av_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms);
275  av_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
276 #endif
277 }
278 
279 
282 static av_cold int read_specific_config(ALSDecContext *ctx)
283 {
284  GetBitContext gb;
285  uint64_t ht_size;
286  int i, config_offset;
287  MPEG4AudioConfig m4ac;
288  ALSSpecificConfig *sconf = &ctx->sconf;
289  AVCodecContext *avctx = ctx->avctx;
290  uint32_t als_id, header_size, trailer_size;
291 
292  init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
293 
294  config_offset = avpriv_mpeg4audio_get_config(&m4ac, avctx->extradata,
295  avctx->extradata_size * 8, 1);
296 
297  if (config_offset < 0)
298  return -1;
299 
300  skip_bits_long(&gb, config_offset);
301 
302  if (get_bits_left(&gb) < (30 << 3))
303  return -1;
304 
305  // read the fixed items
306  als_id = get_bits_long(&gb, 32);
307  avctx->sample_rate = m4ac.sample_rate;
308  skip_bits_long(&gb, 32); // sample rate already known
309  sconf->samples = get_bits_long(&gb, 32);
310  avctx->channels = m4ac.channels;
311  skip_bits(&gb, 16); // number of channels already knwon
312  skip_bits(&gb, 3); // skip file_type
313  sconf->resolution = get_bits(&gb, 3);
314  sconf->floating = get_bits1(&gb);
315  sconf->msb_first = get_bits1(&gb);
316  sconf->frame_length = get_bits(&gb, 16) + 1;
317  sconf->ra_distance = get_bits(&gb, 8);
318  sconf->ra_flag = get_bits(&gb, 2);
319  sconf->adapt_order = get_bits1(&gb);
320  sconf->coef_table = get_bits(&gb, 2);
321  sconf->long_term_prediction = get_bits1(&gb);
322  sconf->max_order = get_bits(&gb, 10);
323  sconf->block_switching = get_bits(&gb, 2);
324  sconf->bgmc = get_bits1(&gb);
325  sconf->sb_part = get_bits1(&gb);
326  sconf->joint_stereo = get_bits1(&gb);
327  sconf->mc_coding = get_bits1(&gb);
328  sconf->chan_config = get_bits1(&gb);
329  sconf->chan_sort = get_bits1(&gb);
330  sconf->crc_enabled = get_bits1(&gb);
331  sconf->rlslms = get_bits1(&gb);
332  skip_bits(&gb, 5); // skip 5 reserved bits
333  skip_bits1(&gb); // skip aux_data_enabled
334 
335 
336  // check for ALSSpecificConfig struct
337  if (als_id != MKBETAG('A','L','S','\0'))
338  return -1;
339 
340  ctx->cur_frame_length = sconf->frame_length;
341 
342  // read channel config
343  if (sconf->chan_config)
344  sconf->chan_config_info = get_bits(&gb, 16);
345  // TODO: use this to set avctx->channel_layout
346 
347 
348  // read channel sorting
349  if (sconf->chan_sort && avctx->channels > 1) {
350  int chan_pos_bits = av_ceil_log2(avctx->channels);
351  int bits_needed = avctx->channels * chan_pos_bits + 7;
352  if (get_bits_left(&gb) < bits_needed)
353  return -1;
354 
355  if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
356  return AVERROR(ENOMEM);
357 
358  for (i = 0; i < avctx->channels; i++)
359  sconf->chan_pos[i] = get_bits(&gb, chan_pos_bits);
360 
361  align_get_bits(&gb);
362  // TODO: use this to actually do channel sorting
363  } else {
364  sconf->chan_sort = 0;
365  }
366 
367 
368  // read fixed header and trailer sizes,
369  // if size = 0xFFFFFFFF then there is no data field!
370  if (get_bits_left(&gb) < 64)
371  return -1;
372 
373  header_size = get_bits_long(&gb, 32);
374  trailer_size = get_bits_long(&gb, 32);
375  if (header_size == 0xFFFFFFFF)
376  header_size = 0;
377  if (trailer_size == 0xFFFFFFFF)
378  trailer_size = 0;
379 
380  ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
381 
382 
383  // skip the header and trailer data
384  if (get_bits_left(&gb) < ht_size)
385  return -1;
386 
387  if (ht_size > INT32_MAX)
388  return -1;
389 
390  skip_bits_long(&gb, ht_size);
391 
392 
393  // initialize CRC calculation
394  if (sconf->crc_enabled) {
395  if (get_bits_left(&gb) < 32)
396  return -1;
397 
398  if (avctx->err_recognition & AV_EF_CRCCHECK) {
399  ctx->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
400  ctx->crc = 0xFFFFFFFF;
401  ctx->crc_org = ~get_bits_long(&gb, 32);
402  } else
403  skip_bits_long(&gb, 32);
404  }
405 
406 
407  // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
408 
409  dprint_specific_config(ctx);
410 
411  return 0;
412 }
413 
414 
417 static int check_specific_config(ALSDecContext *ctx)
418 {
419  ALSSpecificConfig *sconf = &ctx->sconf;
420  int error = 0;
421 
422  // report unsupported feature and set error value
423  #define MISSING_ERR(cond, str, errval) \
424  { \
425  if (cond) { \
426  av_log_missing_feature(ctx->avctx, str, 0); \
427  error = errval; \
428  } \
429  }
430 
431  MISSING_ERR(sconf->floating, "Floating point decoding", AVERROR_PATCHWELCOME);
432  MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME);
433  MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
434 
435  return error;
436 }
437 
438 
442 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
443  unsigned int div, unsigned int **div_blocks,
444  unsigned int *num_blocks)
445 {
446  if (n < 31 && ((bs_info << n) & 0x40000000)) {
447  // if the level is valid and the investigated bit n is set
448  // then recursively check both children at bits (2n+1) and (2n+2)
449  n *= 2;
450  div += 1;
451  parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
452  parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
453  } else {
454  // else the bit is not set or the last level has been reached
455  // (bit implicitly not set)
456  **div_blocks = div;
457  (*div_blocks)++;
458  (*num_blocks)++;
459  }
460 }
461 
462 
465 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
466 {
467  int max = get_bits_left(gb) - k;
468  int q = get_unary(gb, 0, max);
469  int r = k ? get_bits1(gb) : !(q & 1);
470 
471  if (k > 1) {
472  q <<= (k - 1);
473  q += get_bits_long(gb, k - 1);
474  } else if (!k) {
475  q >>= 1;
476  }
477  return r ? q : ~q;
478 }
479 
480 
483 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
484 {
485  int i, j;
486 
487  for (i = 0, j = k - 1; i < j; i++, j--) {
488  int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
489  cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
490  cof[i] += tmp1;
491  }
492  if (i == j)
493  cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
494 
495  cof[k] = par[k];
496 }
497 
498 
503 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
504  uint32_t *bs_info)
505 {
506  ALSSpecificConfig *sconf = &ctx->sconf;
507  GetBitContext *gb = &ctx->gb;
508  unsigned int *ptr_div_blocks = div_blocks;
509  unsigned int b;
510 
511  if (sconf->block_switching) {
512  unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
513  *bs_info = get_bits_long(gb, bs_info_len);
514  *bs_info <<= (32 - bs_info_len);
515  }
516 
517  ctx->num_blocks = 0;
518  parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
519 
520  // The last frame may have an overdetermined block structure given in
521  // the bitstream. In that case the defined block structure would need
522  // more samples than available to be consistent.
523  // The block structure is actually used but the block sizes are adapted
524  // to fit the actual number of available samples.
525  // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
526  // This results in the actual block sizes: 2 2 1 0.
527  // This is not specified in 14496-3 but actually done by the reference
528  // codec RM22 revision 2.
529  // This appears to happen in case of an odd number of samples in the last
530  // frame which is actually not allowed by the block length switching part
531  // of 14496-3.
532  // The ALS conformance files feature an odd number of samples in the last
533  // frame.
534 
535  for (b = 0; b < ctx->num_blocks; b++)
536  div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
537 
538  if (ctx->cur_frame_length != ctx->sconf.frame_length) {
539  unsigned int remaining = ctx->cur_frame_length;
540 
541  for (b = 0; b < ctx->num_blocks; b++) {
542  if (remaining <= div_blocks[b]) {
543  div_blocks[b] = remaining;
544  ctx->num_blocks = b + 1;
545  break;
546  }
547 
548  remaining -= div_blocks[b];
549  }
550  }
551 }
552 
553 
556 static void read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
557 {
558  ALSSpecificConfig *sconf = &ctx->sconf;
559  AVCodecContext *avctx = ctx->avctx;
560  GetBitContext *gb = &ctx->gb;
561 
562  *bd->raw_samples = 0;
563  *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
564  bd->js_blocks = get_bits1(gb);
565 
566  // skip 5 reserved bits
567  skip_bits(gb, 5);
568 
569  if (*bd->const_block) {
570  unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
571  *bd->raw_samples = get_sbits_long(gb, const_val_bits);
572  }
573 
574  // ensure constant block decoding by reusing this field
575  *bd->const_block = 1;
576 }
577 
578 
581 static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
582 {
583  int smp = bd->block_length - 1;
584  int32_t val = *bd->raw_samples;
585  int32_t *dst = bd->raw_samples + 1;
586 
587  // write raw samples into buffer
588  for (; smp; smp--)
589  *dst++ = val;
590 }
591 
592 
595 static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
596 {
597  ALSSpecificConfig *sconf = &ctx->sconf;
598  AVCodecContext *avctx = ctx->avctx;
599  GetBitContext *gb = &ctx->gb;
600  unsigned int k;
601  unsigned int s[8];
602  unsigned int sx[8];
603  unsigned int sub_blocks, log2_sub_blocks, sb_length;
604  unsigned int start = 0;
605  unsigned int opt_order;
606  int sb;
607  int32_t *quant_cof = bd->quant_cof;
608  int32_t *current_res;
609 
610 
611  // ensure variable block decoding by reusing this field
612  *bd->const_block = 0;
613 
614  *bd->opt_order = 1;
615  bd->js_blocks = get_bits1(gb);
616 
617  opt_order = *bd->opt_order;
618 
619  // determine the number of subblocks for entropy decoding
620  if (!sconf->bgmc && !sconf->sb_part) {
621  log2_sub_blocks = 0;
622  } else {
623  if (sconf->bgmc && sconf->sb_part)
624  log2_sub_blocks = get_bits(gb, 2);
625  else
626  log2_sub_blocks = 2 * get_bits1(gb);
627  }
628 
629  sub_blocks = 1 << log2_sub_blocks;
630 
631  // do not continue in case of a damaged stream since
632  // block_length must be evenly divisible by sub_blocks
633  if (bd->block_length & (sub_blocks - 1)) {
634  av_log(avctx, AV_LOG_WARNING,
635  "Block length is not evenly divisible by the number of subblocks.\n");
636  return -1;
637  }
638 
639  sb_length = bd->block_length >> log2_sub_blocks;
640 
641  if (sconf->bgmc) {
642  s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
643  for (k = 1; k < sub_blocks; k++)
644  s[k] = s[k - 1] + decode_rice(gb, 2);
645 
646  for (k = 0; k < sub_blocks; k++) {
647  sx[k] = s[k] & 0x0F;
648  s [k] >>= 4;
649  }
650  } else {
651  s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
652  for (k = 1; k < sub_blocks; k++)
653  s[k] = s[k - 1] + decode_rice(gb, 0);
654  }
655  for (k = 1; k < sub_blocks; k++)
656  if (s[k] > 32) {
657  av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n");
658  return AVERROR_INVALIDDATA;
659  }
660 
661  if (get_bits1(gb))
662  *bd->shift_lsbs = get_bits(gb, 4) + 1;
663 
664  *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
665 
666 
667  if (!sconf->rlslms) {
668  if (sconf->adapt_order) {
669  int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
670  2, sconf->max_order + 1));
671  *bd->opt_order = get_bits(gb, opt_order_length);
672  if (*bd->opt_order > sconf->max_order) {
673  *bd->opt_order = sconf->max_order;
674  av_log(avctx, AV_LOG_ERROR, "Predictor order too large!\n");
675  return AVERROR_INVALIDDATA;
676  }
677  } else {
678  *bd->opt_order = sconf->max_order;
679  }
680 
681  opt_order = *bd->opt_order;
682 
683  if (opt_order) {
684  int add_base;
685 
686  if (sconf->coef_table == 3) {
687  add_base = 0x7F;
688 
689  // read coefficient 0
690  quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
691 
692  // read coefficient 1
693  if (opt_order > 1)
694  quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
695 
696  // read coefficients 2 to opt_order
697  for (k = 2; k < opt_order; k++)
698  quant_cof[k] = get_bits(gb, 7);
699  } else {
700  int k_max;
701  add_base = 1;
702 
703  // read coefficient 0 to 19
704  k_max = FFMIN(opt_order, 20);
705  for (k = 0; k < k_max; k++) {
706  int rice_param = parcor_rice_table[sconf->coef_table][k][1];
707  int offset = parcor_rice_table[sconf->coef_table][k][0];
708  quant_cof[k] = decode_rice(gb, rice_param) + offset;
709  if (quant_cof[k] < -64 || quant_cof[k] > 63) {
710  av_log(avctx, AV_LOG_ERROR, "quant_cof %d is out of range\n", quant_cof[k]);
711  return AVERROR_INVALIDDATA;
712  }
713  }
714 
715  // read coefficients 20 to 126
716  k_max = FFMIN(opt_order, 127);
717  for (; k < k_max; k++)
718  quant_cof[k] = decode_rice(gb, 2) + (k & 1);
719 
720  // read coefficients 127 to opt_order
721  for (; k < opt_order; k++)
722  quant_cof[k] = decode_rice(gb, 1);
723 
724  quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
725 
726  if (opt_order > 1)
727  quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
728  }
729 
730  for (k = 2; k < opt_order; k++)
731  quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
732  }
733  }
734 
735  // read LTP gain and lag values
736  if (sconf->long_term_prediction) {
737  *bd->use_ltp = get_bits1(gb);
738 
739  if (*bd->use_ltp) {
740  int r, c;
741 
742  bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
743  bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
744 
745  r = get_unary(gb, 0, 3);
746  c = get_bits(gb, 2);
747  bd->ltp_gain[2] = ltp_gain_values[r][c];
748 
749  bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
750  bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
751 
752  *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
753  *bd->ltp_lag += FFMAX(4, opt_order + 1);
754  }
755  }
756 
757  // read first value and residuals in case of a random access block
758  if (bd->ra_block) {
759  if (opt_order)
760  bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
761  if (opt_order > 1)
762  bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
763  if (opt_order > 2)
764  bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
765 
766  start = FFMIN(opt_order, 3);
767  }
768 
769  // read all residuals
770  if (sconf->bgmc) {
771  int delta[8];
772  unsigned int k [8];
773  unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
774 
775  // read most significant bits
776  unsigned int high;
777  unsigned int low;
778  unsigned int value;
779 
780  ff_bgmc_decode_init(gb, &high, &low, &value);
781 
782  current_res = bd->raw_samples + start;
783 
784  for (sb = 0; sb < sub_blocks; sb++) {
785  unsigned int sb_len = sb_length - (sb ? 0 : start);
786 
787  k [sb] = s[sb] > b ? s[sb] - b : 0;
788  delta[sb] = 5 - s[sb] + k[sb];
789 
790  ff_bgmc_decode(gb, sb_len, current_res,
791  delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
792 
793  current_res += sb_len;
794  }
795 
796  ff_bgmc_decode_end(gb);
797 
798 
799  // read least significant bits and tails
800  current_res = bd->raw_samples + start;
801 
802  for (sb = 0; sb < sub_blocks; sb++, start = 0) {
803  unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
804  unsigned int cur_k = k[sb];
805  unsigned int cur_s = s[sb];
806 
807  for (; start < sb_length; start++) {
808  int32_t res = *current_res;
809 
810  if (res == cur_tail_code) {
811  unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
812  << (5 - delta[sb]);
813 
814  res = decode_rice(gb, cur_s);
815 
816  if (res >= 0) {
817  res += (max_msb ) << cur_k;
818  } else {
819  res -= (max_msb - 1) << cur_k;
820  }
821  } else {
822  if (res > cur_tail_code)
823  res--;
824 
825  if (res & 1)
826  res = -res;
827 
828  res >>= 1;
829 
830  if (cur_k) {
831  res <<= cur_k;
832  res |= get_bits_long(gb, cur_k);
833  }
834  }
835 
836  *current_res++ = res;
837  }
838  }
839  } else {
840  current_res = bd->raw_samples + start;
841 
842  for (sb = 0; sb < sub_blocks; sb++, start = 0)
843  for (; start < sb_length; start++)
844  *current_res++ = decode_rice(gb, s[sb]);
845  }
846 
847  if (!sconf->mc_coding || ctx->js_switch)
848  align_get_bits(gb);
849 
850  return 0;
851 }
852 
853 
856 static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
857 {
858  ALSSpecificConfig *sconf = &ctx->sconf;
859  unsigned int block_length = bd->block_length;
860  unsigned int smp = 0;
861  unsigned int k;
862  int opt_order = *bd->opt_order;
863  int sb;
864  int64_t y;
865  int32_t *quant_cof = bd->quant_cof;
866  int32_t *lpc_cof = bd->lpc_cof;
867  int32_t *raw_samples = bd->raw_samples;
868  int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
869  int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
870 
871  // reverse long-term prediction
872  if (*bd->use_ltp) {
873  int ltp_smp;
874 
875  for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
876  int center = ltp_smp - *bd->ltp_lag;
877  int begin = FFMAX(0, center - 2);
878  int end = center + 3;
879  int tab = 5 - (end - begin);
880  int base;
881 
882  y = 1 << 6;
883 
884  for (base = begin; base < end; base++, tab++)
885  y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
886 
887  raw_samples[ltp_smp] += y >> 7;
888  }
889  }
890 
891  // reconstruct all samples from residuals
892  if (bd->ra_block) {
893  for (smp = 0; smp < opt_order; smp++) {
894  y = 1 << 19;
895 
896  for (sb = 0; sb < smp; sb++)
897  y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
898 
899  *raw_samples++ -= y >> 20;
900  parcor_to_lpc(smp, quant_cof, lpc_cof);
901  }
902  } else {
903  for (k = 0; k < opt_order; k++)
904  parcor_to_lpc(k, quant_cof, lpc_cof);
905 
906  // store previous samples in case that they have to be altered
907  if (*bd->store_prev_samples)
908  memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
909  sizeof(*bd->prev_raw_samples) * sconf->max_order);
910 
911  // reconstruct difference signal for prediction (joint-stereo)
912  if (bd->js_blocks && bd->raw_other) {
913  int32_t *left, *right;
914 
915  if (bd->raw_other > raw_samples) { // D = R - L
916  left = raw_samples;
917  right = bd->raw_other;
918  } else { // D = R - L
919  left = bd->raw_other;
920  right = raw_samples;
921  }
922 
923  for (sb = -1; sb >= -sconf->max_order; sb--)
924  raw_samples[sb] = right[sb] - left[sb];
925  }
926 
927  // reconstruct shifted signal
928  if (*bd->shift_lsbs)
929  for (sb = -1; sb >= -sconf->max_order; sb--)
930  raw_samples[sb] >>= *bd->shift_lsbs;
931  }
932 
933  // reverse linear prediction coefficients for efficiency
934  lpc_cof = lpc_cof + opt_order;
935 
936  for (sb = 0; sb < opt_order; sb++)
937  lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
938 
939  // reconstruct raw samples
940  raw_samples = bd->raw_samples + smp;
941  lpc_cof = lpc_cof_reversed + opt_order;
942 
943  for (; raw_samples < raw_samples_end; raw_samples++) {
944  y = 1 << 19;
945 
946  for (sb = -opt_order; sb < 0; sb++)
947  y += MUL64(lpc_cof[sb], raw_samples[sb]);
948 
949  *raw_samples -= y >> 20;
950  }
951 
952  raw_samples = bd->raw_samples;
953 
954  // restore previous samples in case that they have been altered
955  if (*bd->store_prev_samples)
956  memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
957  sizeof(*raw_samples) * sconf->max_order);
958 
959  return 0;
960 }
961 
962 
965 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
966 {
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  if (read_var_block_data(ctx, bd))
973  return -1;
974  } else {
975  read_const_block_data(ctx, bd);
976  }
977 
978  return 0;
979 }
980 
981 
984 static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
985 {
986  unsigned int smp;
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 if (decode_var_block_data(ctx, bd))
992  return -1;
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 
1006 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1007 {
1008  int ret;
1009 
1010  ret = read_block(ctx, bd);
1011 
1012  if (ret)
1013  return ret;
1014 
1015  ret = decode_block(ctx, bd);
1016 
1017  return ret;
1018 }
1019 
1020 
1024 static void zero_remaining(unsigned int b, unsigned int b_max,
1025  const unsigned int *div_blocks, int32_t *buf)
1026 {
1027  unsigned int count = 0;
1028 
1029  for (; b < b_max; b++)
1030  count += div_blocks[b];
1031 
1032  if (count)
1033  memset(buf, 0, sizeof(*buf) * count);
1034 }
1035 
1036 
1039 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1040  unsigned int c, const unsigned int *div_blocks,
1041  unsigned int *js_blocks)
1042 {
1043  unsigned int b;
1044  ALSBlockData bd = { 0 };
1045 
1046  bd.ra_block = ra_frame;
1047  bd.const_block = ctx->const_block;
1048  bd.shift_lsbs = ctx->shift_lsbs;
1049  bd.opt_order = ctx->opt_order;
1050  bd.store_prev_samples = ctx->store_prev_samples;
1051  bd.use_ltp = ctx->use_ltp;
1052  bd.ltp_lag = ctx->ltp_lag;
1053  bd.ltp_gain = ctx->ltp_gain[0];
1054  bd.quant_cof = ctx->quant_cof[0];
1055  bd.lpc_cof = ctx->lpc_cof[0];
1056  bd.prev_raw_samples = ctx->prev_raw_samples;
1057  bd.raw_samples = ctx->raw_samples[c];
1058 
1059 
1060  for (b = 0; b < ctx->num_blocks; b++) {
1061  bd.block_length = div_blocks[b];
1062 
1063  if (read_decode_block(ctx, &bd)) {
1064  // damaged block, write zero for the rest of the frame
1065  zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1066  return -1;
1067  }
1068  bd.raw_samples += div_blocks[b];
1069  bd.ra_block = 0;
1070  }
1071 
1072  return 0;
1073 }
1074 
1075 
1078 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1079  unsigned int c, const unsigned int *div_blocks,
1080  unsigned int *js_blocks)
1081 {
1082  ALSSpecificConfig *sconf = &ctx->sconf;
1083  unsigned int offset = 0;
1084  unsigned int b;
1085  ALSBlockData bd[2] = { { 0 } };
1086 
1087  bd[0].ra_block = ra_frame;
1088  bd[0].const_block = ctx->const_block;
1089  bd[0].shift_lsbs = ctx->shift_lsbs;
1090  bd[0].opt_order = ctx->opt_order;
1091  bd[0].store_prev_samples = ctx->store_prev_samples;
1092  bd[0].use_ltp = ctx->use_ltp;
1093  bd[0].ltp_lag = ctx->ltp_lag;
1094  bd[0].ltp_gain = ctx->ltp_gain[0];
1095  bd[0].quant_cof = ctx->quant_cof[0];
1096  bd[0].lpc_cof = ctx->lpc_cof[0];
1097  bd[0].prev_raw_samples = ctx->prev_raw_samples;
1098  bd[0].js_blocks = *js_blocks;
1099 
1100  bd[1].ra_block = ra_frame;
1101  bd[1].const_block = ctx->const_block;
1102  bd[1].shift_lsbs = ctx->shift_lsbs;
1103  bd[1].opt_order = ctx->opt_order;
1104  bd[1].store_prev_samples = ctx->store_prev_samples;
1105  bd[1].use_ltp = ctx->use_ltp;
1106  bd[1].ltp_lag = ctx->ltp_lag;
1107  bd[1].ltp_gain = ctx->ltp_gain[0];
1108  bd[1].quant_cof = ctx->quant_cof[0];
1109  bd[1].lpc_cof = ctx->lpc_cof[0];
1110  bd[1].prev_raw_samples = ctx->prev_raw_samples;
1111  bd[1].js_blocks = *(js_blocks + 1);
1112 
1113  // decode all blocks
1114  for (b = 0; b < ctx->num_blocks; b++) {
1115  unsigned int s;
1116 
1117  bd[0].block_length = div_blocks[b];
1118  bd[1].block_length = div_blocks[b];
1119 
1120  bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1121  bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1122 
1123  bd[0].raw_other = bd[1].raw_samples;
1124  bd[1].raw_other = bd[0].raw_samples;
1125 
1126  if(read_decode_block(ctx, &bd[0]) || read_decode_block(ctx, &bd[1])) {
1127  // damaged block, write zero for the rest of the frame
1128  zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1129  zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1130  return -1;
1131  }
1132 
1133  // reconstruct joint-stereo blocks
1134  if (bd[0].js_blocks) {
1135  if (bd[1].js_blocks)
1136  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair!\n");
1137 
1138  for (s = 0; s < div_blocks[b]; s++)
1139  bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1140  } else if (bd[1].js_blocks) {
1141  for (s = 0; s < div_blocks[b]; s++)
1142  bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1143  }
1144 
1145  offset += div_blocks[b];
1146  bd[0].ra_block = 0;
1147  bd[1].ra_block = 0;
1148  }
1149 
1150  // store carryover raw samples,
1151  // the others channel raw samples are stored by the calling function.
1152  memmove(ctx->raw_samples[c] - sconf->max_order,
1153  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1154  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1155 
1156  return 0;
1157 }
1158 
1159 
1162 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1163 {
1164  GetBitContext *gb = &ctx->gb;
1165  ALSChannelData *current = cd;
1166  unsigned int channels = ctx->avctx->channels;
1167  int entries = 0;
1168 
1169  while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1170  current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1171 
1172  if (current->master_channel >= channels) {
1173  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel!\n");
1174  return -1;
1175  }
1176 
1177  if (current->master_channel != c) {
1178  current->time_diff_flag = get_bits1(gb);
1179  current->weighting[0] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1180  current->weighting[1] = mcc_weightings[av_clip(decode_rice(gb, 2) + 14, 0, 32)];
1181  current->weighting[2] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1182 
1183  if (current->time_diff_flag) {
1184  current->weighting[3] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1185  current->weighting[4] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1186  current->weighting[5] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1187 
1188  current->time_diff_sign = get_bits1(gb);
1189  current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1190  }
1191  }
1192 
1193  current++;
1194  entries++;
1195  }
1196 
1197  if (entries == channels) {
1198  av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data!\n");
1199  return -1;
1200  }
1201 
1202  align_get_bits(gb);
1203  return 0;
1204 }
1205 
1206 
1209 static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1210  ALSChannelData **cd, int *reverted,
1211  unsigned int offset, int c)
1212 {
1213  ALSChannelData *ch = cd[c];
1214  unsigned int dep = 0;
1215  unsigned int channels = ctx->avctx->channels;
1216 
1217  if (reverted[c])
1218  return 0;
1219 
1220  reverted[c] = 1;
1221 
1222  while (dep < channels && !ch[dep].stop_flag) {
1223  revert_channel_correlation(ctx, bd, cd, reverted, offset,
1224  ch[dep].master_channel);
1225 
1226  dep++;
1227  }
1228 
1229  if (dep == channels) {
1230  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation!\n");
1231  return -1;
1232  }
1233 
1234  bd->const_block = ctx->const_block + c;
1235  bd->shift_lsbs = ctx->shift_lsbs + c;
1236  bd->opt_order = ctx->opt_order + c;
1237  bd->store_prev_samples = ctx->store_prev_samples + c;
1238  bd->use_ltp = ctx->use_ltp + c;
1239  bd->ltp_lag = ctx->ltp_lag + c;
1240  bd->ltp_gain = ctx->ltp_gain[c];
1241  bd->lpc_cof = ctx->lpc_cof[c];
1242  bd->quant_cof = ctx->quant_cof[c];
1243  bd->raw_samples = ctx->raw_samples[c] + offset;
1244 
1245  dep = 0;
1246  while (!ch[dep].stop_flag) {
1247  unsigned int smp;
1248  unsigned int begin = 1;
1249  unsigned int end = bd->block_length - 1;
1250  int64_t y;
1251  int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1252 
1253  if (ch[dep].time_diff_flag) {
1254  int t = ch[dep].time_diff_index;
1255 
1256  if (ch[dep].time_diff_sign) {
1257  t = -t;
1258  begin -= t;
1259  } else {
1260  end -= t;
1261  }
1262 
1263  for (smp = begin; smp < end; smp++) {
1264  y = (1 << 6) +
1265  MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1266  MUL64(ch[dep].weighting[1], master[smp ]) +
1267  MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1268  MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1269  MUL64(ch[dep].weighting[4], master[smp + t]) +
1270  MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1271 
1272  bd->raw_samples[smp] += y >> 7;
1273  }
1274  } else {
1275  for (smp = begin; smp < end; smp++) {
1276  y = (1 << 6) +
1277  MUL64(ch[dep].weighting[0], master[smp - 1]) +
1278  MUL64(ch[dep].weighting[1], master[smp ]) +
1279  MUL64(ch[dep].weighting[2], master[smp + 1]);
1280 
1281  bd->raw_samples[smp] += y >> 7;
1282  }
1283  }
1284 
1285  dep++;
1286  }
1287 
1288  return 0;
1289 }
1290 
1291 
1294 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1295 {
1296  ALSSpecificConfig *sconf = &ctx->sconf;
1297  AVCodecContext *avctx = ctx->avctx;
1298  GetBitContext *gb = &ctx->gb;
1299  unsigned int div_blocks[32];
1300  unsigned int c;
1301  unsigned int js_blocks[2];
1302 
1303  uint32_t bs_info = 0;
1304 
1305  // skip the size of the ra unit if present in the frame
1306  if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1307  skip_bits_long(gb, 32);
1308 
1309  if (sconf->mc_coding && sconf->joint_stereo) {
1310  ctx->js_switch = get_bits1(gb);
1311  align_get_bits(gb);
1312  }
1313 
1314  if (!sconf->mc_coding || ctx->js_switch) {
1315  int independent_bs = !sconf->joint_stereo;
1316 
1317  for (c = 0; c < avctx->channels; c++) {
1318  js_blocks[0] = 0;
1319  js_blocks[1] = 0;
1320 
1321  get_block_sizes(ctx, div_blocks, &bs_info);
1322 
1323  // if joint_stereo and block_switching is set, independent decoding
1324  // is signaled via the first bit of bs_info
1325  if (sconf->joint_stereo && sconf->block_switching)
1326  if (bs_info >> 31)
1327  independent_bs = 2;
1328 
1329  // if this is the last channel, it has to be decoded independently
1330  if (c == avctx->channels - 1)
1331  independent_bs = 1;
1332 
1333  if (independent_bs) {
1334  if (decode_blocks_ind(ctx, ra_frame, c, div_blocks, js_blocks))
1335  return -1;
1336 
1337  independent_bs--;
1338  } else {
1339  if (decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks))
1340  return -1;
1341 
1342  c++;
1343  }
1344 
1345  // store carryover raw samples
1346  memmove(ctx->raw_samples[c] - sconf->max_order,
1347  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1348  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1349  }
1350  } else { // multi-channel coding
1351  ALSBlockData bd = { 0 };
1352  int b, ret;
1353  int *reverted_channels = ctx->reverted_channels;
1354  unsigned int offset = 0;
1355 
1356  for (c = 0; c < avctx->channels; c++)
1357  if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1358  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data!\n");
1359  return -1;
1360  }
1361 
1362  memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1363 
1364  bd.ra_block = ra_frame;
1365  bd.prev_raw_samples = ctx->prev_raw_samples;
1366 
1367  get_block_sizes(ctx, div_blocks, &bs_info);
1368 
1369  for (b = 0; b < ctx->num_blocks; b++) {
1370  bd.block_length = div_blocks[b];
1371 
1372  for (c = 0; c < avctx->channels; c++) {
1373  bd.const_block = ctx->const_block + c;
1374  bd.shift_lsbs = ctx->shift_lsbs + c;
1375  bd.opt_order = ctx->opt_order + c;
1376  bd.store_prev_samples = ctx->store_prev_samples + c;
1377  bd.use_ltp = ctx->use_ltp + c;
1378  bd.ltp_lag = ctx->ltp_lag + c;
1379  bd.ltp_gain = ctx->ltp_gain[c];
1380  bd.lpc_cof = ctx->lpc_cof[c];
1381  bd.quant_cof = ctx->quant_cof[c];
1382  bd.raw_samples = ctx->raw_samples[c] + offset;
1383  bd.raw_other = NULL;
1384 
1385  if ((ret = read_block(ctx, &bd)) < 0)
1386  return ret;
1387  if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0)
1388  return ret;
1389  }
1390 
1391  for (c = 0; c < avctx->channels; c++)
1392  if (revert_channel_correlation(ctx, &bd, ctx->chan_data,
1393  reverted_channels, offset, c))
1394  return -1;
1395 
1396  for (c = 0; c < avctx->channels; c++) {
1397  bd.const_block = ctx->const_block + c;
1398  bd.shift_lsbs = ctx->shift_lsbs + c;
1399  bd.opt_order = ctx->opt_order + c;
1400  bd.store_prev_samples = ctx->store_prev_samples + c;
1401  bd.use_ltp = ctx->use_ltp + c;
1402  bd.ltp_lag = ctx->ltp_lag + c;
1403  bd.ltp_gain = ctx->ltp_gain[c];
1404  bd.lpc_cof = ctx->lpc_cof[c];
1405  bd.quant_cof = ctx->quant_cof[c];
1406  bd.raw_samples = ctx->raw_samples[c] + offset;
1407  if ((ret = decode_block(ctx, &bd)) < 0)
1408  return ret;
1409  }
1410 
1411  memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1412  offset += div_blocks[b];
1413  bd.ra_block = 0;
1414  }
1415 
1416  // store carryover raw samples
1417  for (c = 0; c < avctx->channels; c++)
1418  memmove(ctx->raw_samples[c] - sconf->max_order,
1419  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1420  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1421  }
1422 
1423  // TODO: read_diff_float_data
1424 
1425  return 0;
1426 }
1427 
1428 
1431 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1432  AVPacket *avpkt)
1433 {
1434  ALSDecContext *ctx = avctx->priv_data;
1435  ALSSpecificConfig *sconf = &ctx->sconf;
1436  const uint8_t *buffer = avpkt->data;
1437  int buffer_size = avpkt->size;
1438  int invalid_frame, ret;
1439  unsigned int c, sample, ra_frame, bytes_read, shift;
1440 
1441  init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1442 
1443  // In the case that the distance between random access frames is set to zero
1444  // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1445  // For the first frame, if prediction is used, all samples used from the
1446  // previous frame are assumed to be zero.
1447  ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1448 
1449  // the last frame to decode might have a different length
1450  if (sconf->samples != 0xFFFFFFFF)
1451  ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1452  sconf->frame_length);
1453  else
1454  ctx->cur_frame_length = sconf->frame_length;
1455 
1456  // decode the frame data
1457  if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0)
1458  av_log(ctx->avctx, AV_LOG_WARNING,
1459  "Reading frame data failed. Skipping RA unit.\n");
1460 
1461  ctx->frame_id++;
1462 
1463  /* get output buffer */
1464  ctx->frame.nb_samples = ctx->cur_frame_length;
1465  if ((ret = ff_get_buffer(avctx, &ctx->frame)) < 0) {
1466  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
1467  return ret;
1468  }
1469 
1470  // transform decoded frame into output format
1471  #define INTERLEAVE_OUTPUT(bps) \
1472  { \
1473  int##bps##_t *dest = (int##bps##_t*)ctx->frame.data[0]; \
1474  shift = bps - ctx->avctx->bits_per_raw_sample; \
1475  for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1476  for (c = 0; c < avctx->channels; c++) \
1477  *dest++ = ctx->raw_samples[c][sample] << shift; \
1478  }
1479 
1480  if (ctx->avctx->bits_per_raw_sample <= 16) {
1481  INTERLEAVE_OUTPUT(16)
1482  } else {
1483  INTERLEAVE_OUTPUT(32)
1484  }
1485 
1486  // update CRC
1487  if (sconf->crc_enabled && (avctx->err_recognition & AV_EF_CRCCHECK)) {
1488  int swap = HAVE_BIGENDIAN != sconf->msb_first;
1489 
1490  if (ctx->avctx->bits_per_raw_sample == 24) {
1491  int32_t *src = (int32_t *)ctx->frame.data[0];
1492 
1493  for (sample = 0;
1494  sample < ctx->cur_frame_length * avctx->channels;
1495  sample++) {
1496  int32_t v;
1497 
1498  if (swap)
1499  v = av_bswap32(src[sample]);
1500  else
1501  v = src[sample];
1502  if (!HAVE_BIGENDIAN)
1503  v >>= 8;
1504 
1505  ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1506  }
1507  } else {
1508  uint8_t *crc_source;
1509 
1510  if (swap) {
1511  if (ctx->avctx->bits_per_raw_sample <= 16) {
1512  int16_t *src = (int16_t*) ctx->frame.data[0];
1513  int16_t *dest = (int16_t*) ctx->crc_buffer;
1514  for (sample = 0;
1515  sample < ctx->cur_frame_length * avctx->channels;
1516  sample++)
1517  *dest++ = av_bswap16(src[sample]);
1518  } else {
1519  ctx->dsp.bswap_buf((uint32_t*)ctx->crc_buffer,
1520  (uint32_t *)ctx->frame.data[0],
1521  ctx->cur_frame_length * avctx->channels);
1522  }
1523  crc_source = ctx->crc_buffer;
1524  } else {
1525  crc_source = ctx->frame.data[0];
1526  }
1527 
1528  ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1529  ctx->cur_frame_length * avctx->channels *
1530  av_get_bytes_per_sample(avctx->sample_fmt));
1531  }
1532 
1533 
1534  // check CRC sums if this is the last frame
1535  if (ctx->cur_frame_length != sconf->frame_length &&
1536  ctx->crc_org != ctx->crc) {
1537  av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1538  }
1539  }
1540 
1541  *got_frame_ptr = 1;
1542  *(AVFrame *)data = ctx->frame;
1543 
1544 
1545  bytes_read = invalid_frame ? buffer_size :
1546  (get_bits_count(&ctx->gb) + 7) >> 3;
1547 
1548  return bytes_read;
1549 }
1550 
1551 
1554 static av_cold int decode_end(AVCodecContext *avctx)
1555 {
1556  ALSDecContext *ctx = avctx->priv_data;
1557 
1558  av_freep(&ctx->sconf.chan_pos);
1559 
1560  ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1561 
1562  av_freep(&ctx->const_block);
1563  av_freep(&ctx->shift_lsbs);
1564  av_freep(&ctx->opt_order);
1565  av_freep(&ctx->store_prev_samples);
1566  av_freep(&ctx->use_ltp);
1567  av_freep(&ctx->ltp_lag);
1568  av_freep(&ctx->ltp_gain);
1569  av_freep(&ctx->ltp_gain_buffer);
1570  av_freep(&ctx->quant_cof);
1571  av_freep(&ctx->lpc_cof);
1572  av_freep(&ctx->quant_cof_buffer);
1573  av_freep(&ctx->lpc_cof_buffer);
1574  av_freep(&ctx->lpc_cof_reversed_buffer);
1575  av_freep(&ctx->prev_raw_samples);
1576  av_freep(&ctx->raw_samples);
1577  av_freep(&ctx->raw_buffer);
1578  av_freep(&ctx->chan_data);
1579  av_freep(&ctx->chan_data_buffer);
1580  av_freep(&ctx->reverted_channels);
1581  av_freep(&ctx->crc_buffer);
1582 
1583  return 0;
1584 }
1585 
1586 
1589 static av_cold int decode_init(AVCodecContext *avctx)
1590 {
1591  unsigned int c;
1592  unsigned int channel_size;
1593  int num_buffers;
1594  ALSDecContext *ctx = avctx->priv_data;
1595  ALSSpecificConfig *sconf = &ctx->sconf;
1596  ctx->avctx = avctx;
1597 
1598  if (!avctx->extradata) {
1599  av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1600  return -1;
1601  }
1602 
1603  if (read_specific_config(ctx)) {
1604  av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1605  decode_end(avctx);
1606  return -1;
1607  }
1608 
1609  if (check_specific_config(ctx)) {
1610  decode_end(avctx);
1611  return -1;
1612  }
1613 
1614  if (sconf->bgmc)
1615  ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1616 
1617  if (sconf->floating) {
1618  avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1619  avctx->bits_per_raw_sample = 32;
1620  } else {
1621  avctx->sample_fmt = sconf->resolution > 1
1622  ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
1623  avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1624  }
1625 
1626  // set maximum Rice parameter for progressive decoding based on resolution
1627  // This is not specified in 14496-3 but actually done by the reference
1628  // codec RM22 revision 2.
1629  ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1630 
1631  // set lag value for long-term prediction
1632  ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1633  (avctx->sample_rate >= 192000);
1634 
1635  // allocate quantized parcor coefficient buffer
1636  num_buffers = sconf->mc_coding ? avctx->channels : 1;
1637 
1638  ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1639  ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1640  ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1641  num_buffers * sconf->max_order);
1642  ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1643  num_buffers * sconf->max_order);
1644  ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1645  sconf->max_order);
1646 
1647  if (!ctx->quant_cof || !ctx->lpc_cof ||
1648  !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1649  !ctx->lpc_cof_reversed_buffer) {
1650  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1651  return AVERROR(ENOMEM);
1652  }
1653 
1654  // assign quantized parcor coefficient buffers
1655  for (c = 0; c < num_buffers; c++) {
1656  ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1657  ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1658  }
1659 
1660  // allocate and assign lag and gain data buffer for ltp mode
1661  ctx->const_block = av_malloc (sizeof(*ctx->const_block) * num_buffers);
1662  ctx->shift_lsbs = av_malloc (sizeof(*ctx->shift_lsbs) * num_buffers);
1663  ctx->opt_order = av_malloc (sizeof(*ctx->opt_order) * num_buffers);
1664  ctx->store_prev_samples = av_malloc(sizeof(*ctx->store_prev_samples) * num_buffers);
1665  ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1666  ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1667  ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1668  ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1669  num_buffers * 5);
1670 
1671  if (!ctx->const_block || !ctx->shift_lsbs ||
1672  !ctx->opt_order || !ctx->store_prev_samples ||
1673  !ctx->use_ltp || !ctx->ltp_lag ||
1674  !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1675  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1676  decode_end(avctx);
1677  return AVERROR(ENOMEM);
1678  }
1679 
1680  for (c = 0; c < num_buffers; c++)
1681  ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1682 
1683  // allocate and assign channel data buffer for mcc mode
1684  if (sconf->mc_coding) {
1685  ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1686  num_buffers * num_buffers);
1687  ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) *
1688  num_buffers);
1689  ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1690  num_buffers);
1691 
1692  if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1693  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1694  decode_end(avctx);
1695  return AVERROR(ENOMEM);
1696  }
1697 
1698  for (c = 0; c < num_buffers; c++)
1699  ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
1700  } else {
1701  ctx->chan_data = NULL;
1702  ctx->chan_data_buffer = NULL;
1703  ctx->reverted_channels = NULL;
1704  }
1705 
1706  channel_size = sconf->frame_length + sconf->max_order;
1707 
1708  ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1709  ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1710  ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1711 
1712  // allocate previous raw sample buffer
1713  if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1714  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1715  decode_end(avctx);
1716  return AVERROR(ENOMEM);
1717  }
1718 
1719  // assign raw samples buffers
1720  ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1721  for (c = 1; c < avctx->channels; c++)
1722  ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1723 
1724  // allocate crc buffer
1725  if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
1726  (avctx->err_recognition & AV_EF_CRCCHECK)) {
1727  ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) *
1728  ctx->cur_frame_length *
1729  avctx->channels *
1730  av_get_bytes_per_sample(avctx->sample_fmt));
1731  if (!ctx->crc_buffer) {
1732  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1733  decode_end(avctx);
1734  return AVERROR(ENOMEM);
1735  }
1736  }
1737 
1738  ff_dsputil_init(&ctx->dsp, avctx);
1739 
1740  avcodec_get_frame_defaults(&ctx->frame);
1741  avctx->coded_frame = &ctx->frame;
1742 
1743  return 0;
1744 }
1745 
1746 
1749 static av_cold void flush(AVCodecContext *avctx)
1750 {
1751  ALSDecContext *ctx = avctx->priv_data;
1752 
1753  ctx->frame_id = 0;
1754 }
1755 
1756 
1757 AVCodec ff_als_decoder = {
1758  .name = "als",
1759  .type = AVMEDIA_TYPE_AUDIO,
1760  .id = AV_CODEC_ID_MP4ALS,
1761  .priv_data_size = sizeof(ALSDecContext),
1762  .init = decode_init,
1763  .close = decode_end,
1764  .decode = decode_frame,
1765  .flush = flush,
1766  .capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
1767  .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),
1768 };