FFmpeg
alsdec.c
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1 /*
2  * MPEG-4 ALS decoder
3  * Copyright (c) 2009 Thilo Borgmann <thilo.borgmann _at_ mail.de>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * MPEG-4 ALS decoder
25  * @author Thilo Borgmann <thilo.borgmann _at_ mail.de>
26  */
27 
28 #include <inttypes.h>
29 
30 #include "avcodec.h"
31 #include "get_bits.h"
32 #include "unary.h"
33 #include "mpeg4audio.h"
34 #include "bgmc.h"
35 #include "bswapdsp.h"
36 #include "internal.h"
37 #include "mlz.h"
38 #include "libavutil/samplefmt.h"
39 #include "libavutil/crc.h"
41 #include "libavutil/intfloat.h"
42 #include "libavutil/intreadwrite.h"
43 
44 #include <stdint.h>
45 
46 /** Rice parameters and corresponding index offsets for decoding the
47  * indices of scaled PARCOR values. The table chosen is set globally
48  * by the encoder and stored in ALSSpecificConfig.
49  */
50 static const int8_t parcor_rice_table[3][20][2] = {
51  { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
52  { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
53  { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
54  { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
55  { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
56  { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
57  {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
58  { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
59  { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
60  { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
61  {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
62  { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
63 };
64 
65 
66 /** Scaled PARCOR values used for the first two PARCOR coefficients.
67  * To be indexed by the Rice coded indices.
68  * Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20)
69  * Actual values are divided by 32 in order to be stored in 16 bits.
70  */
71 static const int16_t parcor_scaled_values[] = {
72  -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
73  -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
74  -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
75  -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
76  -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
77  -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
78  -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
79  -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
80  -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
81  -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
82  -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
83  -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
84  -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
85  -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
86  -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
87  -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
88  -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
89  -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
90  -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
91  -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
92  -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
93  -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
94  -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
95  46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
96  143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
97  244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
98  349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
99  458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
100  571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
101  688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
102  810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
103  935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
104 };
105 
106 
107 /** Gain values of p(0) for long-term prediction.
108  * To be indexed by the Rice coded indices.
109  */
110 static const uint8_t ltp_gain_values [4][4] = {
111  { 0, 8, 16, 24},
112  {32, 40, 48, 56},
113  {64, 70, 76, 82},
114  {88, 92, 96, 100}
115 };
116 
117 
118 /** Inter-channel weighting factors for multi-channel correlation.
119  * To be indexed by the Rice coded indices.
120  */
121 static const int16_t mcc_weightings[] = {
122  204, 192, 179, 166, 153, 140, 128, 115,
123  102, 89, 76, 64, 51, 38, 25, 12,
124  0, -12, -25, -38, -51, -64, -76, -89,
125  -102, -115, -128, -140, -153, -166, -179, -192
126 };
127 
128 
129 /** Tail codes used in arithmetic coding using block Gilbert-Moore codes.
130  */
131 static const uint8_t tail_code[16][6] = {
132  { 74, 44, 25, 13, 7, 3},
133  { 68, 42, 24, 13, 7, 3},
134  { 58, 39, 23, 13, 7, 3},
135  {126, 70, 37, 19, 10, 5},
136  {132, 70, 37, 20, 10, 5},
137  {124, 70, 38, 20, 10, 5},
138  {120, 69, 37, 20, 11, 5},
139  {116, 67, 37, 20, 11, 5},
140  {108, 66, 36, 20, 10, 5},
141  {102, 62, 36, 20, 10, 5},
142  { 88, 58, 34, 19, 10, 5},
143  {162, 89, 49, 25, 13, 7},
144  {156, 87, 49, 26, 14, 7},
145  {150, 86, 47, 26, 14, 7},
146  {142, 84, 47, 26, 14, 7},
147  {131, 79, 46, 26, 14, 7}
148 };
149 
150 
151 enum RA_Flag {
155 };
156 
157 
158 typedef struct ALSSpecificConfig {
159  uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown
160  int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
161  int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer
162  int msb_first; ///< 1 = original CRC calculated on big-endian system, 0 = little-endian
163  int frame_length; ///< frame length for each frame (last frame may differ)
164  int ra_distance; ///< distance between RA frames (in frames, 0...255)
165  enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored
166  int adapt_order; ///< adaptive order: 1 = on, 0 = off
167  int coef_table; ///< table index of Rice code parameters
168  int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off
169  int max_order; ///< maximum prediction order (0..1023)
170  int block_switching; ///< number of block switching levels
171  int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
172  int sb_part; ///< sub-block partition
173  int joint_stereo; ///< joint stereo: 1 = on, 0 = off
174  int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off
175  int chan_config; ///< indicates that a chan_config_info field is present
176  int chan_sort; ///< channel rearrangement: 1 = on, 0 = off
177  int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
178  int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented.
179  int *chan_pos; ///< original channel positions
180  int crc_enabled; ///< enable Cyclic Redundancy Checksum
182 
183 
184 typedef struct ALSChannelData {
190  int weighting[6];
192 
193 
194 typedef struct ALSDecContext {
199  const AVCRC *crc_table;
200  uint32_t crc_org; ///< CRC value of the original input data
201  uint32_t crc; ///< CRC value calculated from decoded data
202  unsigned int cur_frame_length; ///< length of the current frame to decode
203  unsigned int frame_id; ///< the frame ID / number of the current frame
204  unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
205  unsigned int cs_switch; ///< if true, channel rearrangement is done
206  unsigned int num_blocks; ///< number of blocks used in the current frame
207  unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding
208  uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
209  int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
210  int ltp_lag_length; ///< number of bits used for ltp lag value
211  int *const_block; ///< contains const_block flags for all channels
212  unsigned int *shift_lsbs; ///< contains shift_lsbs flags for all channels
213  unsigned int *opt_order; ///< contains opt_order flags for all channels
214  int *store_prev_samples; ///< contains store_prev_samples flags for all channels
215  int *use_ltp; ///< contains use_ltp flags for all channels
216  int *ltp_lag; ///< contains ltp lag values for all channels
217  int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
218  int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
219  int32_t **quant_cof; ///< quantized parcor coefficients for a channel
220  int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
221  int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
222  int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
223  int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
224  ALSChannelData **chan_data; ///< channel data for multi-channel correlation
225  ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
226  int *reverted_channels; ///< stores a flag for each reverted channel
227  int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
228  int32_t **raw_samples; ///< decoded raw samples for each channel
229  int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
230  uint8_t *crc_buffer; ///< buffer of byte order corrected samples used for CRC check
231  MLZ* mlz; ///< masked lz decompression structure
232  SoftFloat_IEEE754 *acf; ///< contains common multiplier for all channels
233  int *last_acf_mantissa; ///< contains the last acf mantissa data of common multiplier for all channels
234  int *shift_value; ///< value by which the binary point is to be shifted for all channels
235  int *last_shift_value; ///< contains last shift value for all channels
236  int **raw_mantissa; ///< decoded mantissa bits of the difference signal
237  unsigned char *larray; ///< buffer to store the output of masked lz decompression
238  int *nbits; ///< contains the number of bits to read for masked lz decompression for all samples
240 } ALSDecContext;
241 
242 
243 typedef struct ALSBlockData {
244  unsigned int block_length; ///< number of samples within the block
245  unsigned int ra_block; ///< if true, this is a random access block
246  int *const_block; ///< if true, this is a constant value block
247  int js_blocks; ///< true if this block contains a difference signal
248  unsigned int *shift_lsbs; ///< shift of values for this block
249  unsigned int *opt_order; ///< prediction order of this block
250  int *store_prev_samples;///< if true, carryover samples have to be stored
251  int *use_ltp; ///< if true, long-term prediction is used
252  int *ltp_lag; ///< lag value for long-term prediction
253  int *ltp_gain; ///< gain values for ltp 5-tap filter
254  int32_t *quant_cof; ///< quantized parcor coefficients
255  int32_t *lpc_cof; ///< coefficients of the direct form prediction
256  int32_t *raw_samples; ///< decoded raw samples / residuals for this block
257  int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
258  int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
259 } ALSBlockData;
260 
261 
263 {
264 #ifdef DEBUG
265  AVCodecContext *avctx = ctx->avctx;
266  ALSSpecificConfig *sconf = &ctx->sconf;
267 
268  ff_dlog(avctx, "resolution = %i\n", sconf->resolution);
269  ff_dlog(avctx, "floating = %i\n", sconf->floating);
270  ff_dlog(avctx, "frame_length = %i\n", sconf->frame_length);
271  ff_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance);
272  ff_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag);
273  ff_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order);
274  ff_dlog(avctx, "coef_table = %i\n", sconf->coef_table);
275  ff_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
276  ff_dlog(avctx, "max_order = %i\n", sconf->max_order);
277  ff_dlog(avctx, "block_switching = %i\n", sconf->block_switching);
278  ff_dlog(avctx, "bgmc = %i\n", sconf->bgmc);
279  ff_dlog(avctx, "sb_part = %i\n", sconf->sb_part);
280  ff_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
281  ff_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding);
282  ff_dlog(avctx, "chan_config = %i\n", sconf->chan_config);
283  ff_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort);
284  ff_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms);
285  ff_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
286 #endif
287 }
288 
289 
290 /** Read an ALSSpecificConfig from a buffer into the output struct.
291  */
293 {
294  GetBitContext gb;
295  uint64_t ht_size;
296  int i, config_offset;
297  MPEG4AudioConfig m4ac = {0};
298  ALSSpecificConfig *sconf = &ctx->sconf;
299  AVCodecContext *avctx = ctx->avctx;
300  uint32_t als_id, header_size, trailer_size;
301  int ret;
302 
303  if ((ret = init_get_bits8(&gb, avctx->extradata, avctx->extradata_size)) < 0)
304  return ret;
305 
306  config_offset = avpriv_mpeg4audio_get_config2(&m4ac, avctx->extradata,
307  avctx->extradata_size, 1, avctx);
308 
309  if (config_offset < 0)
310  return AVERROR_INVALIDDATA;
311 
312  skip_bits_long(&gb, config_offset);
313 
314  if (get_bits_left(&gb) < (30 << 3))
315  return AVERROR_INVALIDDATA;
316 
317  // read the fixed items
318  als_id = get_bits_long(&gb, 32);
319  avctx->sample_rate = m4ac.sample_rate;
320  skip_bits_long(&gb, 32); // sample rate already known
321  sconf->samples = get_bits_long(&gb, 32);
322  avctx->channels = m4ac.channels;
323  skip_bits(&gb, 16); // number of channels already known
324  skip_bits(&gb, 3); // skip file_type
325  sconf->resolution = get_bits(&gb, 3);
326  sconf->floating = get_bits1(&gb);
327  sconf->msb_first = get_bits1(&gb);
328  sconf->frame_length = get_bits(&gb, 16) + 1;
329  sconf->ra_distance = get_bits(&gb, 8);
330  sconf->ra_flag = get_bits(&gb, 2);
331  sconf->adapt_order = get_bits1(&gb);
332  sconf->coef_table = get_bits(&gb, 2);
333  sconf->long_term_prediction = get_bits1(&gb);
334  sconf->max_order = get_bits(&gb, 10);
335  sconf->block_switching = get_bits(&gb, 2);
336  sconf->bgmc = get_bits1(&gb);
337  sconf->sb_part = get_bits1(&gb);
338  sconf->joint_stereo = get_bits1(&gb);
339  sconf->mc_coding = get_bits1(&gb);
340  sconf->chan_config = get_bits1(&gb);
341  sconf->chan_sort = get_bits1(&gb);
342  sconf->crc_enabled = get_bits1(&gb);
343  sconf->rlslms = get_bits1(&gb);
344  skip_bits(&gb, 5); // skip 5 reserved bits
345  skip_bits1(&gb); // skip aux_data_enabled
346 
347 
348  // check for ALSSpecificConfig struct
349  if (als_id != MKBETAG('A','L','S','\0'))
350  return AVERROR_INVALIDDATA;
351 
352  if (avctx->channels > FF_SANE_NB_CHANNELS) {
353  avpriv_request_sample(avctx, "Huge number of channels");
354  return AVERROR_PATCHWELCOME;
355  }
356 
357  ctx->cur_frame_length = sconf->frame_length;
358 
359  // read channel config
360  if (sconf->chan_config)
361  sconf->chan_config_info = get_bits(&gb, 16);
362  // TODO: use this to set avctx->channel_layout
363 
364 
365  // read channel sorting
366  if (sconf->chan_sort && avctx->channels > 1) {
367  int chan_pos_bits = av_ceil_log2(avctx->channels);
368  int bits_needed = avctx->channels * chan_pos_bits + 7;
369  if (get_bits_left(&gb) < bits_needed)
370  return AVERROR_INVALIDDATA;
371 
372  if (!(sconf->chan_pos = av_malloc_array(avctx->channels, sizeof(*sconf->chan_pos))))
373  return AVERROR(ENOMEM);
374 
375  ctx->cs_switch = 1;
376 
377  for (i = 0; i < avctx->channels; i++) {
378  sconf->chan_pos[i] = -1;
379  }
380 
381  for (i = 0; i < avctx->channels; i++) {
382  int idx;
383 
384  idx = get_bits(&gb, chan_pos_bits);
385  if (idx >= avctx->channels || sconf->chan_pos[idx] != -1) {
386  av_log(avctx, AV_LOG_WARNING, "Invalid channel reordering.\n");
387  ctx->cs_switch = 0;
388  break;
389  }
390  sconf->chan_pos[idx] = i;
391  }
392 
393  align_get_bits(&gb);
394  }
395 
396 
397  // read fixed header and trailer sizes,
398  // if size = 0xFFFFFFFF then there is no data field!
399  if (get_bits_left(&gb) < 64)
400  return AVERROR_INVALIDDATA;
401 
402  header_size = get_bits_long(&gb, 32);
403  trailer_size = get_bits_long(&gb, 32);
404  if (header_size == 0xFFFFFFFF)
405  header_size = 0;
406  if (trailer_size == 0xFFFFFFFF)
407  trailer_size = 0;
408 
409  ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
410 
411 
412  // skip the header and trailer data
413  if (get_bits_left(&gb) < ht_size)
414  return AVERROR_INVALIDDATA;
415 
416  if (ht_size > INT32_MAX)
417  return AVERROR_PATCHWELCOME;
418 
419  skip_bits_long(&gb, ht_size);
420 
421 
422  // initialize CRC calculation
423  if (sconf->crc_enabled) {
424  if (get_bits_left(&gb) < 32)
425  return AVERROR_INVALIDDATA;
426 
429  ctx->crc = 0xFFFFFFFF;
430  ctx->crc_org = ~get_bits_long(&gb, 32);
431  } else
432  skip_bits_long(&gb, 32);
433  }
434 
435 
436  // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
437 
439 
440  return 0;
441 }
442 
443 
444 /** Check the ALSSpecificConfig for unsupported features.
445  */
447 {
448  ALSSpecificConfig *sconf = &ctx->sconf;
449  int error = 0;
450 
451  // report unsupported feature and set error value
452  #define MISSING_ERR(cond, str, errval) \
453  { \
454  if (cond) { \
455  avpriv_report_missing_feature(ctx->avctx, \
456  str); \
457  error = errval; \
458  } \
459  }
460 
461  MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME);
462 
463  return error;
464 }
465 
466 
467 /** Parse the bs_info field to extract the block partitioning used in
468  * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
469  */
470 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
471  unsigned int div, unsigned int **div_blocks,
472  unsigned int *num_blocks)
473 {
474  if (n < 31 && ((bs_info << n) & 0x40000000)) {
475  // if the level is valid and the investigated bit n is set
476  // then recursively check both children at bits (2n+1) and (2n+2)
477  n *= 2;
478  div += 1;
479  parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
480  parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
481  } else {
482  // else the bit is not set or the last level has been reached
483  // (bit implicitly not set)
484  **div_blocks = div;
485  (*div_blocks)++;
486  (*num_blocks)++;
487  }
488 }
489 
490 
491 /** Read and decode a Rice codeword.
492  */
493 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
494 {
495  int max = get_bits_left(gb) - k;
496  unsigned q = get_unary(gb, 0, max);
497  int r = k ? get_bits1(gb) : !(q & 1);
498 
499  if (k > 1) {
500  q <<= (k - 1);
501  q += get_bits_long(gb, k - 1);
502  } else if (!k) {
503  q >>= 1;
504  }
505  return r ? q : ~q;
506 }
507 
508 
509 /** Convert PARCOR coefficient k to direct filter coefficient.
510  */
511 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
512 {
513  int i, j;
514 
515  for (i = 0, j = k - 1; i < j; i++, j--) {
516  unsigned tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
517  cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
518  cof[i] += tmp1;
519  }
520  if (i == j)
521  cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
522 
523  cof[k] = par[k];
524 }
525 
526 
527 /** Read block switching field if necessary and set actual block sizes.
528  * Also assure that the block sizes of the last frame correspond to the
529  * actual number of samples.
530  */
531 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
532  uint32_t *bs_info)
533 {
534  ALSSpecificConfig *sconf = &ctx->sconf;
535  GetBitContext *gb = &ctx->gb;
536  unsigned int *ptr_div_blocks = div_blocks;
537  unsigned int b;
538 
539  if (sconf->block_switching) {
540  unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
541  *bs_info = get_bits_long(gb, bs_info_len);
542  *bs_info <<= (32 - bs_info_len);
543  }
544 
545  ctx->num_blocks = 0;
546  parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
547 
548  // The last frame may have an overdetermined block structure given in
549  // the bitstream. In that case the defined block structure would need
550  // more samples than available to be consistent.
551  // The block structure is actually used but the block sizes are adapted
552  // to fit the actual number of available samples.
553  // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
554  // This results in the actual block sizes: 2 2 1 0.
555  // This is not specified in 14496-3 but actually done by the reference
556  // codec RM22 revision 2.
557  // This appears to happen in case of an odd number of samples in the last
558  // frame which is actually not allowed by the block length switching part
559  // of 14496-3.
560  // The ALS conformance files feature an odd number of samples in the last
561  // frame.
562 
563  for (b = 0; b < ctx->num_blocks; b++)
564  div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
565 
566  if (ctx->cur_frame_length != ctx->sconf.frame_length) {
567  unsigned int remaining = ctx->cur_frame_length;
568 
569  for (b = 0; b < ctx->num_blocks; b++) {
570  if (remaining <= div_blocks[b]) {
571  div_blocks[b] = remaining;
572  ctx->num_blocks = b + 1;
573  break;
574  }
575 
576  remaining -= div_blocks[b];
577  }
578  }
579 }
580 
581 
582 /** Read the block data for a constant block
583  */
585 {
586  ALSSpecificConfig *sconf = &ctx->sconf;
587  AVCodecContext *avctx = ctx->avctx;
588  GetBitContext *gb = &ctx->gb;
589 
590  if (bd->block_length <= 0)
591  return AVERROR_INVALIDDATA;
592 
593  *bd->raw_samples = 0;
594  *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
595  bd->js_blocks = get_bits1(gb);
596 
597  // skip 5 reserved bits
598  skip_bits(gb, 5);
599 
600  if (*bd->const_block) {
601  unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
602  *bd->raw_samples = get_sbits_long(gb, const_val_bits);
603  }
604 
605  // ensure constant block decoding by reusing this field
606  *bd->const_block = 1;
607 
608  return 0;
609 }
610 
611 
612 /** Decode the block data for a constant block
613  */
615 {
616  int smp = bd->block_length - 1;
617  int32_t val = *bd->raw_samples;
618  int32_t *dst = bd->raw_samples + 1;
619 
620  // write raw samples into buffer
621  for (; smp; smp--)
622  *dst++ = val;
623 }
624 
625 
626 /** Read the block data for a non-constant block
627  */
629 {
630  ALSSpecificConfig *sconf = &ctx->sconf;
631  AVCodecContext *avctx = ctx->avctx;
632  GetBitContext *gb = &ctx->gb;
633  unsigned int k;
634  unsigned int s[8];
635  unsigned int sx[8];
636  unsigned int sub_blocks, log2_sub_blocks, sb_length;
637  unsigned int start = 0;
638  unsigned int opt_order;
639  int sb;
640  int32_t *quant_cof = bd->quant_cof;
641  int32_t *current_res;
642 
643 
644  // ensure variable block decoding by reusing this field
645  *bd->const_block = 0;
646 
647  *bd->opt_order = 1;
648  bd->js_blocks = get_bits1(gb);
649 
650  opt_order = *bd->opt_order;
651 
652  // determine the number of subblocks for entropy decoding
653  if (!sconf->bgmc && !sconf->sb_part) {
654  log2_sub_blocks = 0;
655  } else {
656  if (sconf->bgmc && sconf->sb_part)
657  log2_sub_blocks = get_bits(gb, 2);
658  else
659  log2_sub_blocks = 2 * get_bits1(gb);
660  }
661 
662  sub_blocks = 1 << log2_sub_blocks;
663 
664  // do not continue in case of a damaged stream since
665  // block_length must be evenly divisible by sub_blocks
666  if (bd->block_length & (sub_blocks - 1) || bd->block_length <= 0) {
667  av_log(avctx, AV_LOG_WARNING,
668  "Block length is not evenly divisible by the number of subblocks.\n");
669  return AVERROR_INVALIDDATA;
670  }
671 
672  sb_length = bd->block_length >> log2_sub_blocks;
673 
674  if (sconf->bgmc) {
675  s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
676  for (k = 1; k < sub_blocks; k++)
677  s[k] = s[k - 1] + decode_rice(gb, 2);
678 
679  for (k = 0; k < sub_blocks; k++) {
680  sx[k] = s[k] & 0x0F;
681  s [k] >>= 4;
682  }
683  } else {
684  s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
685  for (k = 1; k < sub_blocks; k++)
686  s[k] = s[k - 1] + decode_rice(gb, 0);
687  }
688  for (k = 1; k < sub_blocks; k++)
689  if (s[k] > 32) {
690  av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n");
691  return AVERROR_INVALIDDATA;
692  }
693 
694  if (get_bits1(gb))
695  *bd->shift_lsbs = get_bits(gb, 4) + 1;
696 
697  *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
698 
699 
700  if (!sconf->rlslms) {
701  if (sconf->adapt_order && sconf->max_order) {
702  int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
703  2, sconf->max_order + 1));
704  *bd->opt_order = get_bits(gb, opt_order_length);
705  if (*bd->opt_order > sconf->max_order) {
706  *bd->opt_order = sconf->max_order;
707  av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n");
708  return AVERROR_INVALIDDATA;
709  }
710  } else {
711  *bd->opt_order = sconf->max_order;
712  }
713  opt_order = *bd->opt_order;
714 
715  if (opt_order) {
716  int add_base;
717 
718  if (sconf->coef_table == 3) {
719  add_base = 0x7F;
720 
721  // read coefficient 0
722  quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
723 
724  // read coefficient 1
725  if (opt_order > 1)
726  quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
727 
728  // read coefficients 2 to opt_order
729  for (k = 2; k < opt_order; k++)
730  quant_cof[k] = get_bits(gb, 7);
731  } else {
732  int k_max;
733  add_base = 1;
734 
735  // read coefficient 0 to 19
736  k_max = FFMIN(opt_order, 20);
737  for (k = 0; k < k_max; k++) {
738  int rice_param = parcor_rice_table[sconf->coef_table][k][1];
739  int offset = parcor_rice_table[sconf->coef_table][k][0];
740  quant_cof[k] = decode_rice(gb, rice_param) + offset;
741  if (quant_cof[k] < -64 || quant_cof[k] > 63) {
742  av_log(avctx, AV_LOG_ERROR,
743  "quant_cof %"PRId32" is out of range.\n",
744  quant_cof[k]);
745  return AVERROR_INVALIDDATA;
746  }
747  }
748 
749  // read coefficients 20 to 126
750  k_max = FFMIN(opt_order, 127);
751  for (; k < k_max; k++)
752  quant_cof[k] = decode_rice(gb, 2) + (k & 1);
753 
754  // read coefficients 127 to opt_order
755  for (; k < opt_order; k++)
756  quant_cof[k] = decode_rice(gb, 1);
757 
758  quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
759 
760  if (opt_order > 1)
761  quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
762  }
763 
764  for (k = 2; k < opt_order; k++)
765  quant_cof[k] = (quant_cof[k] * (1 << 14)) + (add_base << 13);
766  }
767  }
768 
769  // read LTP gain and lag values
770  if (sconf->long_term_prediction) {
771  *bd->use_ltp = get_bits1(gb);
772 
773  if (*bd->use_ltp) {
774  int r, c;
775 
776  bd->ltp_gain[0] = decode_rice(gb, 1) * 8;
777  bd->ltp_gain[1] = decode_rice(gb, 2) * 8;
778 
779  r = get_unary(gb, 0, 4);
780  c = get_bits(gb, 2);
781  if (r >= 4) {
782  av_log(avctx, AV_LOG_ERROR, "r overflow\n");
783  return AVERROR_INVALIDDATA;
784  }
785 
786  bd->ltp_gain[2] = ltp_gain_values[r][c];
787 
788  bd->ltp_gain[3] = decode_rice(gb, 2) * 8;
789  bd->ltp_gain[4] = decode_rice(gb, 1) * 8;
790 
791  *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
792  *bd->ltp_lag += FFMAX(4, opt_order + 1);
793  }
794  }
795 
796  // read first value and residuals in case of a random access block
797  if (bd->ra_block) {
798  start = FFMIN(opt_order, 3);
799  av_assert0(sb_length <= sconf->frame_length);
800  if (sb_length <= start) {
801  // opt_order or sb_length may be corrupted, either way this is unsupported and not well defined in the specification
802  av_log(avctx, AV_LOG_ERROR, "Sub block length smaller or equal start\n");
803  return AVERROR_PATCHWELCOME;
804  }
805 
806  if (opt_order)
807  bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
808  if (opt_order > 1)
809  bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
810  if (opt_order > 2)
811  bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
812  }
813 
814  // read all residuals
815  if (sconf->bgmc) {
816  int delta[8];
817  unsigned int k [8];
818  unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
819 
820  // read most significant bits
821  unsigned int high;
822  unsigned int low;
823  unsigned int value;
824 
825  int ret = ff_bgmc_decode_init(gb, &high, &low, &value);
826  if (ret < 0)
827  return ret;
828 
829  current_res = bd->raw_samples + start;
830 
831  for (sb = 0; sb < sub_blocks; sb++) {
832  unsigned int sb_len = sb_length - (sb ? 0 : start);
833 
834  k [sb] = s[sb] > b ? s[sb] - b : 0;
835  delta[sb] = 5 - s[sb] + k[sb];
836 
837  if (k[sb] >= 32)
838  return AVERROR_INVALIDDATA;
839 
840  ff_bgmc_decode(gb, sb_len, current_res,
841  delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
842 
843  current_res += sb_len;
844  }
845 
846  ff_bgmc_decode_end(gb);
847 
848 
849  // read least significant bits and tails
850  current_res = bd->raw_samples + start;
851 
852  for (sb = 0; sb < sub_blocks; sb++, start = 0) {
853  unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
854  unsigned int cur_k = k[sb];
855  unsigned int cur_s = s[sb];
856 
857  for (; start < sb_length; start++) {
858  int32_t res = *current_res;
859 
860  if (res == cur_tail_code) {
861  unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
862  << (5 - delta[sb]);
863 
864  res = decode_rice(gb, cur_s);
865 
866  if (res >= 0) {
867  res += (max_msb ) << cur_k;
868  } else {
869  res -= (max_msb - 1) << cur_k;
870  }
871  } else {
872  if (res > cur_tail_code)
873  res--;
874 
875  if (res & 1)
876  res = -res;
877 
878  res >>= 1;
879 
880  if (cur_k) {
881  res *= 1U << cur_k;
882  res |= get_bits_long(gb, cur_k);
883  }
884  }
885 
886  *current_res++ = res;
887  }
888  }
889  } else {
890  current_res = bd->raw_samples + start;
891 
892  for (sb = 0; sb < sub_blocks; sb++, start = 0)
893  for (; start < sb_length; start++)
894  *current_res++ = decode_rice(gb, s[sb]);
895  }
896 
897  return 0;
898 }
899 
900 
901 /** Decode the block data for a non-constant block
902  */
904 {
905  ALSSpecificConfig *sconf = &ctx->sconf;
906  unsigned int block_length = bd->block_length;
907  unsigned int smp = 0;
908  unsigned int k;
909  int opt_order = *bd->opt_order;
910  int sb;
911  int64_t y;
912  int32_t *quant_cof = bd->quant_cof;
913  int32_t *lpc_cof = bd->lpc_cof;
914  int32_t *raw_samples = bd->raw_samples;
915  int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
916  int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
917 
918  // reverse long-term prediction
919  if (*bd->use_ltp) {
920  int ltp_smp;
921 
922  for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
923  int center = ltp_smp - *bd->ltp_lag;
924  int begin = FFMAX(0, center - 2);
925  int end = center + 3;
926  int tab = 5 - (end - begin);
927  int base;
928 
929  y = 1 << 6;
930 
931  for (base = begin; base < end; base++, tab++)
932  y += (uint64_t)MUL64(bd->ltp_gain[tab], raw_samples[base]);
933 
934  raw_samples[ltp_smp] += y >> 7;
935  }
936  }
937 
938  // reconstruct all samples from residuals
939  if (bd->ra_block) {
940  for (smp = 0; smp < FFMIN(opt_order, block_length); smp++) {
941  y = 1 << 19;
942 
943  for (sb = 0; sb < smp; sb++)
944  y += (uint64_t)MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
945 
946  *raw_samples++ -= y >> 20;
947  parcor_to_lpc(smp, quant_cof, lpc_cof);
948  }
949  } else {
950  for (k = 0; k < opt_order; k++)
951  parcor_to_lpc(k, quant_cof, lpc_cof);
952 
953  // store previous samples in case that they have to be altered
954  if (*bd->store_prev_samples)
955  memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
956  sizeof(*bd->prev_raw_samples) * sconf->max_order);
957 
958  // reconstruct difference signal for prediction (joint-stereo)
959  if (bd->js_blocks && bd->raw_other) {
960  uint32_t *left, *right;
961 
962  if (bd->raw_other > raw_samples) { // D = R - L
963  left = raw_samples;
964  right = bd->raw_other;
965  } else { // D = R - L
966  left = bd->raw_other;
967  right = raw_samples;
968  }
969 
970  for (sb = -1; sb >= -sconf->max_order; sb--)
971  raw_samples[sb] = right[sb] - left[sb];
972  }
973 
974  // reconstruct shifted signal
975  if (*bd->shift_lsbs)
976  for (sb = -1; sb >= -sconf->max_order; sb--)
977  raw_samples[sb] >>= *bd->shift_lsbs;
978  }
979 
980  // reverse linear prediction coefficients for efficiency
981  lpc_cof = lpc_cof + opt_order;
982 
983  for (sb = 0; sb < opt_order; sb++)
984  lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
985 
986  // reconstruct raw samples
987  raw_samples = bd->raw_samples + smp;
988  lpc_cof = lpc_cof_reversed + opt_order;
989 
990  for (; raw_samples < raw_samples_end; raw_samples++) {
991  y = 1 << 19;
992 
993  for (sb = -opt_order; sb < 0; sb++)
994  y += (uint64_t)MUL64(lpc_cof[sb], raw_samples[sb]);
995 
996  *raw_samples -= y >> 20;
997  }
998 
999  raw_samples = bd->raw_samples;
1000 
1001  // restore previous samples in case that they have been altered
1002  if (*bd->store_prev_samples)
1003  memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
1004  sizeof(*raw_samples) * sconf->max_order);
1005 
1006  return 0;
1007 }
1008 
1009 
1010 /** Read the block data.
1011  */
1013 {
1014  int ret;
1015  GetBitContext *gb = &ctx->gb;
1016  ALSSpecificConfig *sconf = &ctx->sconf;
1017 
1018  *bd->shift_lsbs = 0;
1019  // read block type flag and read the samples accordingly
1020  if (get_bits1(gb)) {
1021  ret = read_var_block_data(ctx, bd);
1022  } else {
1023  ret = read_const_block_data(ctx, bd);
1024  }
1025 
1026  if (!sconf->mc_coding || ctx->js_switch)
1027  align_get_bits(gb);
1028 
1029  return ret;
1030 }
1031 
1032 
1033 /** Decode the block data.
1034  */
1036 {
1037  unsigned int smp;
1038  int ret = 0;
1039 
1040  // read block type flag and read the samples accordingly
1041  if (*bd->const_block)
1042  decode_const_block_data(ctx, bd);
1043  else
1044  ret = decode_var_block_data(ctx, bd); // always return 0
1045 
1046  if (ret < 0)
1047  return ret;
1048 
1049  // TODO: read RLSLMS extension data
1050 
1051  if (*bd->shift_lsbs)
1052  for (smp = 0; smp < bd->block_length; smp++)
1053  bd->raw_samples[smp] = (unsigned)bd->raw_samples[smp] << *bd->shift_lsbs;
1054 
1055  return 0;
1056 }
1057 
1058 
1059 /** Read and decode block data successively.
1060  */
1062 {
1063  int ret;
1064 
1065  if ((ret = read_block(ctx, bd)) < 0)
1066  return ret;
1067 
1068  return decode_block(ctx, bd);
1069 }
1070 
1071 
1072 /** Compute the number of samples left to decode for the current frame and
1073  * sets these samples to zero.
1074  */
1075 static void zero_remaining(unsigned int b, unsigned int b_max,
1076  const unsigned int *div_blocks, int32_t *buf)
1077 {
1078  unsigned int count = 0;
1079 
1080  while (b < b_max)
1081  count += div_blocks[b++];
1082 
1083  if (count)
1084  memset(buf, 0, sizeof(*buf) * count);
1085 }
1086 
1087 
1088 /** Decode blocks independently.
1089  */
1090 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1091  unsigned int c, const unsigned int *div_blocks,
1092  unsigned int *js_blocks)
1093 {
1094  int ret;
1095  unsigned int b;
1096  ALSBlockData bd = { 0 };
1097 
1098  bd.ra_block = ra_frame;
1099  bd.const_block = ctx->const_block;
1100  bd.shift_lsbs = ctx->shift_lsbs;
1101  bd.opt_order = ctx->opt_order;
1103  bd.use_ltp = ctx->use_ltp;
1104  bd.ltp_lag = ctx->ltp_lag;
1105  bd.ltp_gain = ctx->ltp_gain[0];
1106  bd.quant_cof = ctx->quant_cof[0];
1107  bd.lpc_cof = ctx->lpc_cof[0];
1109  bd.raw_samples = ctx->raw_samples[c];
1110 
1111 
1112  for (b = 0; b < ctx->num_blocks; b++) {
1113  bd.block_length = div_blocks[b];
1114 
1115  if ((ret = read_decode_block(ctx, &bd)) < 0) {
1116  // damaged block, write zero for the rest of the frame
1117  zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1118  return ret;
1119  }
1120  bd.raw_samples += div_blocks[b];
1121  bd.ra_block = 0;
1122  }
1123 
1124  return 0;
1125 }
1126 
1127 
1128 /** Decode blocks dependently.
1129  */
1130 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1131  unsigned int c, const unsigned int *div_blocks,
1132  unsigned int *js_blocks)
1133 {
1134  ALSSpecificConfig *sconf = &ctx->sconf;
1135  unsigned int offset = 0;
1136  unsigned int b;
1137  int ret;
1138  ALSBlockData bd[2] = { { 0 } };
1139 
1140  bd[0].ra_block = ra_frame;
1141  bd[0].const_block = ctx->const_block;
1142  bd[0].shift_lsbs = ctx->shift_lsbs;
1143  bd[0].opt_order = ctx->opt_order;
1145  bd[0].use_ltp = ctx->use_ltp;
1146  bd[0].ltp_lag = ctx->ltp_lag;
1147  bd[0].ltp_gain = ctx->ltp_gain[0];
1148  bd[0].quant_cof = ctx->quant_cof[0];
1149  bd[0].lpc_cof = ctx->lpc_cof[0];
1150  bd[0].prev_raw_samples = ctx->prev_raw_samples;
1151  bd[0].js_blocks = *js_blocks;
1152 
1153  bd[1].ra_block = ra_frame;
1154  bd[1].const_block = ctx->const_block;
1155  bd[1].shift_lsbs = ctx->shift_lsbs;
1156  bd[1].opt_order = ctx->opt_order;
1158  bd[1].use_ltp = ctx->use_ltp;
1159  bd[1].ltp_lag = ctx->ltp_lag;
1160  bd[1].ltp_gain = ctx->ltp_gain[0];
1161  bd[1].quant_cof = ctx->quant_cof[0];
1162  bd[1].lpc_cof = ctx->lpc_cof[0];
1163  bd[1].prev_raw_samples = ctx->prev_raw_samples;
1164  bd[1].js_blocks = *(js_blocks + 1);
1165 
1166  // decode all blocks
1167  for (b = 0; b < ctx->num_blocks; b++) {
1168  unsigned int s;
1169 
1170  bd[0].block_length = div_blocks[b];
1171  bd[1].block_length = div_blocks[b];
1172 
1173  bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1174  bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1175 
1176  bd[0].raw_other = bd[1].raw_samples;
1177  bd[1].raw_other = bd[0].raw_samples;
1178 
1179  if ((ret = read_decode_block(ctx, &bd[0])) < 0 ||
1180  (ret = read_decode_block(ctx, &bd[1])) < 0)
1181  goto fail;
1182 
1183  // reconstruct joint-stereo blocks
1184  if (bd[0].js_blocks) {
1185  if (bd[1].js_blocks)
1186  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair.\n");
1187 
1188  for (s = 0; s < div_blocks[b]; s++)
1189  bd[0].raw_samples[s] = bd[1].raw_samples[s] - (unsigned)bd[0].raw_samples[s];
1190  } else if (bd[1].js_blocks) {
1191  for (s = 0; s < div_blocks[b]; s++)
1192  bd[1].raw_samples[s] = bd[1].raw_samples[s] + (unsigned)bd[0].raw_samples[s];
1193  }
1194 
1195  offset += div_blocks[b];
1196  bd[0].ra_block = 0;
1197  bd[1].ra_block = 0;
1198  }
1199 
1200  // store carryover raw samples,
1201  // the others channel raw samples are stored by the calling function.
1202  memmove(ctx->raw_samples[c] - sconf->max_order,
1203  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1204  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1205 
1206  return 0;
1207 fail:
1208  // damaged block, write zero for the rest of the frame
1209  zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1210  zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1211  return ret;
1212 }
1213 
1214 static inline int als_weighting(GetBitContext *gb, int k, int off)
1215 {
1216  int idx = av_clip(decode_rice(gb, k) + off,
1217  0, FF_ARRAY_ELEMS(mcc_weightings) - 1);
1218  return mcc_weightings[idx];
1219 }
1220 
1221 /** Read the channel data.
1222  */
1224 {
1225  GetBitContext *gb = &ctx->gb;
1226  ALSChannelData *current = cd;
1227  unsigned int channels = ctx->avctx->channels;
1228  int entries = 0;
1229 
1230  while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1231  current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1232 
1233  if (current->master_channel >= channels) {
1234  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel.\n");
1235  return AVERROR_INVALIDDATA;
1236  }
1237 
1238  if (current->master_channel != c) {
1239  current->time_diff_flag = get_bits1(gb);
1240  current->weighting[0] = als_weighting(gb, 1, 16);
1241  current->weighting[1] = als_weighting(gb, 2, 14);
1242  current->weighting[2] = als_weighting(gb, 1, 16);
1243 
1244  if (current->time_diff_flag) {
1245  current->weighting[3] = als_weighting(gb, 1, 16);
1246  current->weighting[4] = als_weighting(gb, 1, 16);
1247  current->weighting[5] = als_weighting(gb, 1, 16);
1248 
1249  current->time_diff_sign = get_bits1(gb);
1250  current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1251  }
1252  }
1253 
1254  current++;
1255  entries++;
1256  }
1257 
1258  if (entries == channels) {
1259  av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data.\n");
1260  return AVERROR_INVALIDDATA;
1261  }
1262 
1263  align_get_bits(gb);
1264  return 0;
1265 }
1266 
1267 
1268 /** Recursively reverts the inter-channel correlation for a block.
1269  */
1271  ALSChannelData **cd, int *reverted,
1272  unsigned int offset, int c)
1273 {
1274  ALSChannelData *ch = cd[c];
1275  unsigned int dep = 0;
1276  unsigned int channels = ctx->avctx->channels;
1277  unsigned int channel_size = ctx->sconf.frame_length + ctx->sconf.max_order;
1278 
1279  if (reverted[c])
1280  return 0;
1281 
1282  reverted[c] = 1;
1283 
1284  while (dep < channels && !ch[dep].stop_flag) {
1285  revert_channel_correlation(ctx, bd, cd, reverted, offset,
1286  ch[dep].master_channel);
1287 
1288  dep++;
1289  }
1290 
1291  if (dep == channels) {
1292  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation.\n");
1293  return AVERROR_INVALIDDATA;
1294  }
1295 
1296  bd->const_block = ctx->const_block + c;
1297  bd->shift_lsbs = ctx->shift_lsbs + c;
1298  bd->opt_order = ctx->opt_order + c;
1300  bd->use_ltp = ctx->use_ltp + c;
1301  bd->ltp_lag = ctx->ltp_lag + c;
1302  bd->ltp_gain = ctx->ltp_gain[c];
1303  bd->lpc_cof = ctx->lpc_cof[c];
1304  bd->quant_cof = ctx->quant_cof[c];
1305  bd->raw_samples = ctx->raw_samples[c] + offset;
1306 
1307  for (dep = 0; !ch[dep].stop_flag; dep++) {
1308  ptrdiff_t smp;
1309  ptrdiff_t begin = 1;
1310  ptrdiff_t end = bd->block_length - 1;
1311  int64_t y;
1312  int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1313 
1314  if (ch[dep].master_channel == c)
1315  continue;
1316 
1317  if (ch[dep].time_diff_flag) {
1318  int t = ch[dep].time_diff_index;
1319 
1320  if (ch[dep].time_diff_sign) {
1321  t = -t;
1322  if (begin < t) {
1323  av_log(ctx->avctx, AV_LOG_ERROR, "begin %"PTRDIFF_SPECIFIER" smaller than time diff index %d.\n", begin, t);
1324  return AVERROR_INVALIDDATA;
1325  }
1326  begin -= t;
1327  } else {
1328  if (end < t) {
1329  av_log(ctx->avctx, AV_LOG_ERROR, "end %"PTRDIFF_SPECIFIER" smaller than time diff index %d.\n", end, t);
1330  return AVERROR_INVALIDDATA;
1331  }
1332  end -= t;
1333  }
1334 
1335  if (FFMIN(begin - 1, begin - 1 + t) < ctx->raw_buffer - master ||
1336  FFMAX(end + 1, end + 1 + t) > ctx->raw_buffer + channels * channel_size - master) {
1337  av_log(ctx->avctx, AV_LOG_ERROR,
1338  "sample pointer range [%p, %p] not contained in raw_buffer [%p, %p].\n",
1339  master + FFMIN(begin - 1, begin - 1 + t), master + FFMAX(end + 1, end + 1 + t),
1340  ctx->raw_buffer, ctx->raw_buffer + channels * channel_size);
1341  return AVERROR_INVALIDDATA;
1342  }
1343 
1344  for (smp = begin; smp < end; smp++) {
1345  y = (1 << 6) +
1346  MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1347  MUL64(ch[dep].weighting[1], master[smp ]) +
1348  MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1349  MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1350  MUL64(ch[dep].weighting[4], master[smp + t]) +
1351  MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1352 
1353  bd->raw_samples[smp] += y >> 7;
1354  }
1355  } else {
1356 
1357  if (begin - 1 < ctx->raw_buffer - master ||
1358  end + 1 > ctx->raw_buffer + channels * channel_size - master) {
1359  av_log(ctx->avctx, AV_LOG_ERROR,
1360  "sample pointer range [%p, %p] not contained in raw_buffer [%p, %p].\n",
1361  master + begin - 1, master + end + 1,
1362  ctx->raw_buffer, ctx->raw_buffer + channels * channel_size);
1363  return AVERROR_INVALIDDATA;
1364  }
1365 
1366  for (smp = begin; smp < end; smp++) {
1367  y = (1 << 6) +
1368  MUL64(ch[dep].weighting[0], master[smp - 1]) +
1369  MUL64(ch[dep].weighting[1], master[smp ]) +
1370  MUL64(ch[dep].weighting[2], master[smp + 1]);
1371 
1372  bd->raw_samples[smp] += y >> 7;
1373  }
1374  }
1375  }
1376 
1377  return 0;
1378 }
1379 
1380 
1381 /** multiply two softfloats and handle the rounding off
1382  */
1384  uint64_t mantissa_temp;
1385  uint64_t mask_64;
1386  int cutoff_bit_count;
1387  unsigned char last_2_bits;
1388  unsigned int mantissa;
1389  int32_t sign;
1390  uint32_t return_val = 0;
1391  int bit_count = 48;
1392 
1393  sign = a.sign ^ b.sign;
1394 
1395  // Multiply mantissa bits in a 64-bit register
1396  mantissa_temp = (uint64_t)a.mant * (uint64_t)b.mant;
1397  mask_64 = (uint64_t)0x1 << 47;
1398 
1399  if (!mantissa_temp)
1400  return FLOAT_0;
1401 
1402  // Count the valid bit count
1403  while (!(mantissa_temp & mask_64) && mask_64) {
1404  bit_count--;
1405  mask_64 >>= 1;
1406  }
1407 
1408  // Round off
1409  cutoff_bit_count = bit_count - 24;
1410  if (cutoff_bit_count > 0) {
1411  last_2_bits = (unsigned char)(((unsigned int)mantissa_temp >> (cutoff_bit_count - 1)) & 0x3 );
1412  if ((last_2_bits == 0x3) || ((last_2_bits == 0x1) && ((unsigned int)mantissa_temp & ((0x1UL << (cutoff_bit_count - 1)) - 1)))) {
1413  // Need to round up
1414  mantissa_temp += (uint64_t)0x1 << cutoff_bit_count;
1415  }
1416  }
1417 
1418  if (cutoff_bit_count >= 0) {
1419  mantissa = (unsigned int)(mantissa_temp >> cutoff_bit_count);
1420  } else {
1421  mantissa = (unsigned int)(mantissa_temp <<-cutoff_bit_count);
1422  }
1423 
1424  // Need one more shift?
1425  if (mantissa & 0x01000000ul) {
1426  bit_count++;
1427  mantissa >>= 1;
1428  }
1429 
1430  if (!sign) {
1431  return_val = 0x80000000U;
1432  }
1433 
1434  return_val |= ((unsigned)av_clip(a.exp + b.exp + bit_count - 47, -126, 127) << 23) & 0x7F800000;
1435  return_val |= mantissa;
1436  return av_bits2sf_ieee754(return_val);
1437 }
1438 
1439 
1440 /** Read and decode the floating point sample data
1441  */
1442 static int read_diff_float_data(ALSDecContext *ctx, unsigned int ra_frame) {
1443  AVCodecContext *avctx = ctx->avctx;
1444  GetBitContext *gb = &ctx->gb;
1445  SoftFloat_IEEE754 *acf = ctx->acf;
1446  int *shift_value = ctx->shift_value;
1447  int *last_shift_value = ctx->last_shift_value;
1448  int *last_acf_mantissa = ctx->last_acf_mantissa;
1449  int **raw_mantissa = ctx->raw_mantissa;
1450  int *nbits = ctx->nbits;
1451  unsigned char *larray = ctx->larray;
1452  int frame_length = ctx->cur_frame_length;
1453  SoftFloat_IEEE754 scale = av_int2sf_ieee754(0x1u, 23);
1454  unsigned int partA_flag;
1455  unsigned int highest_byte;
1456  unsigned int shift_amp;
1457  uint32_t tmp_32;
1458  int use_acf;
1459  int nchars;
1460  int i;
1461  int c;
1462  long k;
1463  long nbits_aligned;
1464  unsigned long acc;
1465  unsigned long j;
1466  uint32_t sign;
1467  uint32_t e;
1468  uint32_t mantissa;
1469 
1470  skip_bits_long(gb, 32); //num_bytes_diff_float
1471  use_acf = get_bits1(gb);
1472 
1473  if (ra_frame) {
1474  memset(last_acf_mantissa, 0, avctx->channels * sizeof(*last_acf_mantissa));
1475  memset(last_shift_value, 0, avctx->channels * sizeof(*last_shift_value) );
1476  ff_mlz_flush_dict(ctx->mlz);
1477  }
1478 
1479  if (avctx->channels * 8 > get_bits_left(gb))
1480  return AVERROR_INVALIDDATA;
1481 
1482  for (c = 0; c < avctx->channels; ++c) {
1483  if (use_acf) {
1484  //acf_flag
1485  if (get_bits1(gb)) {
1486  tmp_32 = get_bits(gb, 23);
1487  last_acf_mantissa[c] = tmp_32;
1488  } else {
1489  tmp_32 = last_acf_mantissa[c];
1490  }
1491  acf[c] = av_bits2sf_ieee754(tmp_32);
1492  } else {
1493  acf[c] = FLOAT_1;
1494  }
1495 
1496  highest_byte = get_bits(gb, 2);
1497  partA_flag = get_bits1(gb);
1498  shift_amp = get_bits1(gb);
1499 
1500  if (shift_amp) {
1501  shift_value[c] = get_bits(gb, 8);
1502  last_shift_value[c] = shift_value[c];
1503  } else {
1504  shift_value[c] = last_shift_value[c];
1505  }
1506 
1507  if (partA_flag) {
1508  if (!get_bits1(gb)) { //uncompressed
1509  for (i = 0; i < frame_length; ++i) {
1510  if (ctx->raw_samples[c][i] == 0) {
1511  ctx->raw_mantissa[c][i] = get_bits_long(gb, 32);
1512  }
1513  }
1514  } else { //compressed
1515  nchars = 0;
1516  for (i = 0; i < frame_length; ++i) {
1517  if (ctx->raw_samples[c][i] == 0) {
1518  nchars += 4;
1519  }
1520  }
1521 
1522  tmp_32 = ff_mlz_decompression(ctx->mlz, gb, nchars, larray);
1523  if(tmp_32 != nchars) {
1524  av_log(ctx->avctx, AV_LOG_ERROR, "Error in MLZ decompression (%"PRId32", %d).\n", tmp_32, nchars);
1525  return AVERROR_INVALIDDATA;
1526  }
1527 
1528  for (i = 0; i < frame_length; ++i) {
1529  ctx->raw_mantissa[c][i] = AV_RB32(larray);
1530  }
1531  }
1532  }
1533 
1534  //decode part B
1535  if (highest_byte) {
1536  for (i = 0; i < frame_length; ++i) {
1537  if (ctx->raw_samples[c][i] != 0) {
1538  //The following logic is taken from Tabel 14.45 and 14.46 from the ISO spec
1539  if (av_cmp_sf_ieee754(acf[c], FLOAT_1)) {
1540  nbits[i] = 23 - av_log2(abs(ctx->raw_samples[c][i]));
1541  } else {
1542  nbits[i] = 23;
1543  }
1544  nbits[i] = FFMIN(nbits[i], highest_byte*8);
1545  }
1546  }
1547 
1548  if (!get_bits1(gb)) { //uncompressed
1549  for (i = 0; i < frame_length; ++i) {
1550  if (ctx->raw_samples[c][i] != 0) {
1551  raw_mantissa[c][i] = get_bitsz(gb, nbits[i]);
1552  }
1553  }
1554  } else { //compressed
1555  nchars = 0;
1556  for (i = 0; i < frame_length; ++i) {
1557  if (ctx->raw_samples[c][i]) {
1558  nchars += (int) nbits[i] / 8;
1559  if (nbits[i] & 7) {
1560  ++nchars;
1561  }
1562  }
1563  }
1564 
1565  tmp_32 = ff_mlz_decompression(ctx->mlz, gb, nchars, larray);
1566  if(tmp_32 != nchars) {
1567  av_log(ctx->avctx, AV_LOG_ERROR, "Error in MLZ decompression (%"PRId32", %d).\n", tmp_32, nchars);
1568  return AVERROR_INVALIDDATA;
1569  }
1570 
1571  j = 0;
1572  for (i = 0; i < frame_length; ++i) {
1573  if (ctx->raw_samples[c][i]) {
1574  if (nbits[i] & 7) {
1575  nbits_aligned = 8 * ((unsigned int)(nbits[i] / 8) + 1);
1576  } else {
1577  nbits_aligned = nbits[i];
1578  }
1579  acc = 0;
1580  for (k = 0; k < nbits_aligned/8; ++k) {
1581  acc = (acc << 8) + larray[j++];
1582  }
1583  acc >>= (nbits_aligned - nbits[i]);
1584  raw_mantissa[c][i] = acc;
1585  }
1586  }
1587  }
1588  }
1589 
1590  for (i = 0; i < frame_length; ++i) {
1591  SoftFloat_IEEE754 pcm_sf = av_int2sf_ieee754(ctx->raw_samples[c][i], 0);
1592  pcm_sf = av_div_sf_ieee754(pcm_sf, scale);
1593 
1594  if (ctx->raw_samples[c][i] != 0) {
1595  if (!av_cmp_sf_ieee754(acf[c], FLOAT_1)) {
1596  pcm_sf = multiply(acf[c], pcm_sf);
1597  }
1598 
1599  sign = pcm_sf.sign;
1600  e = pcm_sf.exp;
1601  mantissa = (pcm_sf.mant | 0x800000) + raw_mantissa[c][i];
1602 
1603  while(mantissa >= 0x1000000) {
1604  e++;
1605  mantissa >>= 1;
1606  }
1607 
1608  if (mantissa) e += (shift_value[c] - 127);
1609  mantissa &= 0x007fffffUL;
1610 
1611  tmp_32 = (sign << 31) | ((e + EXP_BIAS) << 23) | (mantissa);
1612  ctx->raw_samples[c][i] = tmp_32;
1613  } else {
1614  ctx->raw_samples[c][i] = raw_mantissa[c][i] & 0x007fffffUL;
1615  }
1616  }
1617  align_get_bits(gb);
1618  }
1619  return 0;
1620 }
1621 
1622 
1623 /** Read the frame data.
1624  */
1625 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1626 {
1627  ALSSpecificConfig *sconf = &ctx->sconf;
1628  AVCodecContext *avctx = ctx->avctx;
1629  GetBitContext *gb = &ctx->gb;
1630  unsigned int div_blocks[32]; ///< block sizes.
1631  unsigned int c;
1632  unsigned int js_blocks[2];
1633  uint32_t bs_info = 0;
1634  int ret;
1635 
1636  // skip the size of the ra unit if present in the frame
1637  if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1638  skip_bits_long(gb, 32);
1639 
1640  if (sconf->mc_coding && sconf->joint_stereo) {
1641  ctx->js_switch = get_bits1(gb);
1642  align_get_bits(gb);
1643  }
1644 
1645  if (!sconf->mc_coding || ctx->js_switch) {
1646  int independent_bs = !sconf->joint_stereo;
1647 
1648  for (c = 0; c < avctx->channels; c++) {
1649  js_blocks[0] = 0;
1650  js_blocks[1] = 0;
1651 
1652  get_block_sizes(ctx, div_blocks, &bs_info);
1653 
1654  // if joint_stereo and block_switching is set, independent decoding
1655  // is signaled via the first bit of bs_info
1656  if (sconf->joint_stereo && sconf->block_switching)
1657  if (bs_info >> 31)
1658  independent_bs = 2;
1659 
1660  // if this is the last channel, it has to be decoded independently
1661  if (c == avctx->channels - 1 || (c & 1))
1662  independent_bs = 1;
1663 
1664  if (independent_bs) {
1665  ret = decode_blocks_ind(ctx, ra_frame, c,
1666  div_blocks, js_blocks);
1667  if (ret < 0)
1668  return ret;
1669  independent_bs--;
1670  } else {
1671  ret = decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks);
1672  if (ret < 0)
1673  return ret;
1674 
1675  c++;
1676  }
1677 
1678  // store carryover raw samples
1679  memmove(ctx->raw_samples[c] - sconf->max_order,
1680  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1681  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1682  ctx->highest_decoded_channel = c;
1683  }
1684  } else { // multi-channel coding
1685  ALSBlockData bd = { 0 };
1686  int b, ret;
1687  int *reverted_channels = ctx->reverted_channels;
1688  unsigned int offset = 0;
1689 
1690  for (c = 0; c < avctx->channels; c++)
1691  if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1692  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data.\n");
1693  return AVERROR_INVALIDDATA;
1694  }
1695 
1696  memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1697 
1698  bd.ra_block = ra_frame;
1700 
1701  get_block_sizes(ctx, div_blocks, &bs_info);
1702 
1703  for (b = 0; b < ctx->num_blocks; b++) {
1704  bd.block_length = div_blocks[b];
1705  if (bd.block_length <= 0) {
1706  av_log(ctx->avctx, AV_LOG_WARNING,
1707  "Invalid block length %u in channel data!\n",
1708  bd.block_length);
1709  continue;
1710  }
1711 
1712  for (c = 0; c < avctx->channels; c++) {
1713  bd.const_block = ctx->const_block + c;
1714  bd.shift_lsbs = ctx->shift_lsbs + c;
1715  bd.opt_order = ctx->opt_order + c;
1717  bd.use_ltp = ctx->use_ltp + c;
1718  bd.ltp_lag = ctx->ltp_lag + c;
1719  bd.ltp_gain = ctx->ltp_gain[c];
1720  bd.lpc_cof = ctx->lpc_cof[c];
1721  bd.quant_cof = ctx->quant_cof[c];
1722  bd.raw_samples = ctx->raw_samples[c] + offset;
1723  bd.raw_other = NULL;
1724 
1725  if ((ret = read_block(ctx, &bd)) < 0)
1726  return ret;
1727  if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0)
1728  return ret;
1729  }
1730 
1731  for (c = 0; c < avctx->channels; c++) {
1732  ret = revert_channel_correlation(ctx, &bd, ctx->chan_data,
1733  reverted_channels, offset, c);
1734  if (ret < 0)
1735  return ret;
1736  }
1737  for (c = 0; c < avctx->channels; c++) {
1738  bd.const_block = ctx->const_block + c;
1739  bd.shift_lsbs = ctx->shift_lsbs + c;
1740  bd.opt_order = ctx->opt_order + c;
1742  bd.use_ltp = ctx->use_ltp + c;
1743  bd.ltp_lag = ctx->ltp_lag + c;
1744  bd.ltp_gain = ctx->ltp_gain[c];
1745  bd.lpc_cof = ctx->lpc_cof[c];
1746  bd.quant_cof = ctx->quant_cof[c];
1747  bd.raw_samples = ctx->raw_samples[c] + offset;
1748 
1749  if ((ret = decode_block(ctx, &bd)) < 0)
1750  return ret;
1751 
1753  }
1754 
1755  memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1756  offset += div_blocks[b];
1757  bd.ra_block = 0;
1758  }
1759 
1760  // store carryover raw samples
1761  for (c = 0; c < avctx->channels; c++)
1762  memmove(ctx->raw_samples[c] - sconf->max_order,
1763  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1764  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1765  }
1766 
1767  if (sconf->floating) {
1768  read_diff_float_data(ctx, ra_frame);
1769  }
1770 
1771  if (get_bits_left(gb) < 0) {
1772  av_log(ctx->avctx, AV_LOG_ERROR, "Overread %d\n", -get_bits_left(gb));
1773  return AVERROR_INVALIDDATA;
1774  }
1775 
1776  return 0;
1777 }
1778 
1779 
1780 /** Decode an ALS frame.
1781  */
1782 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1783  AVPacket *avpkt)
1784 {
1785  ALSDecContext *ctx = avctx->priv_data;
1786  AVFrame *frame = data;
1787  ALSSpecificConfig *sconf = &ctx->sconf;
1788  const uint8_t *buffer = avpkt->data;
1789  int buffer_size = avpkt->size;
1790  int invalid_frame, ret;
1791  unsigned int c, sample, ra_frame, bytes_read, shift;
1792 
1793  if ((ret = init_get_bits8(&ctx->gb, buffer, buffer_size)) < 0)
1794  return ret;
1795 
1796  // In the case that the distance between random access frames is set to zero
1797  // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1798  // For the first frame, if prediction is used, all samples used from the
1799  // previous frame are assumed to be zero.
1800  ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1801 
1802  // the last frame to decode might have a different length
1803  if (sconf->samples != 0xFFFFFFFF)
1804  ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1805  sconf->frame_length);
1806  else
1807  ctx->cur_frame_length = sconf->frame_length;
1808 
1809  ctx->highest_decoded_channel = 0;
1810  // decode the frame data
1811  if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0)
1812  av_log(ctx->avctx, AV_LOG_WARNING,
1813  "Reading frame data failed. Skipping RA unit.\n");
1814 
1815  if (ctx->highest_decoded_channel == 0)
1816  return AVERROR_INVALIDDATA;
1817 
1818  ctx->frame_id++;
1819 
1820  /* get output buffer */
1821  frame->nb_samples = ctx->cur_frame_length;
1822  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
1823  return ret;
1824 
1825  // transform decoded frame into output format
1826  #define INTERLEAVE_OUTPUT(bps) \
1827  { \
1828  int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \
1829  int channels = avctx->channels; \
1830  int32_t *raw_samples = ctx->raw_samples[0]; \
1831  int raw_step = channels > 1 ? ctx->raw_samples[1] - raw_samples : 1; \
1832  shift = bps - ctx->avctx->bits_per_raw_sample; \
1833  if (!ctx->cs_switch) { \
1834  for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1835  for (c = 0; c < channels; c++) \
1836  *dest++ = raw_samples[c*raw_step + sample] * (1U << shift); \
1837  } else { \
1838  for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1839  for (c = 0; c < channels; c++) \
1840  *dest++ = raw_samples[sconf->chan_pos[c]*raw_step + sample] * (1U << shift);\
1841  } \
1842  }
1843 
1844  if (ctx->avctx->bits_per_raw_sample <= 16) {
1845  INTERLEAVE_OUTPUT(16)
1846  } else {
1847  INTERLEAVE_OUTPUT(32)
1848  }
1849 
1850  // update CRC
1851  if (sconf->crc_enabled && (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
1852  int swap = HAVE_BIGENDIAN != sconf->msb_first;
1853 
1854  if (ctx->avctx->bits_per_raw_sample == 24) {
1855  int32_t *src = (int32_t *)frame->data[0];
1856 
1857  for (sample = 0;
1858  sample < ctx->cur_frame_length * avctx->channels;
1859  sample++) {
1860  int32_t v;
1861 
1862  if (swap)
1863  v = av_bswap32(src[sample]);
1864  else
1865  v = src[sample];
1866  if (!HAVE_BIGENDIAN)
1867  v >>= 8;
1868 
1869  ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1870  }
1871  } else {
1872  uint8_t *crc_source;
1873 
1874  if (swap) {
1875  if (ctx->avctx->bits_per_raw_sample <= 16) {
1876  int16_t *src = (int16_t*) frame->data[0];
1877  int16_t *dest = (int16_t*) ctx->crc_buffer;
1878  for (sample = 0;
1879  sample < ctx->cur_frame_length * avctx->channels;
1880  sample++)
1881  *dest++ = av_bswap16(src[sample]);
1882  } else {
1883  ctx->bdsp.bswap_buf((uint32_t *) ctx->crc_buffer,
1884  (uint32_t *) frame->data[0],
1885  ctx->cur_frame_length * avctx->channels);
1886  }
1887  crc_source = ctx->crc_buffer;
1888  } else {
1889  crc_source = frame->data[0];
1890  }
1891 
1892  ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1893  ctx->cur_frame_length * avctx->channels *
1895  }
1896 
1897 
1898  // check CRC sums if this is the last frame
1899  if (ctx->cur_frame_length != sconf->frame_length &&
1900  ctx->crc_org != ctx->crc) {
1901  av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1902  if (avctx->err_recognition & AV_EF_EXPLODE)
1903  return AVERROR_INVALIDDATA;
1904  }
1905  }
1906 
1907  *got_frame_ptr = 1;
1908 
1909  bytes_read = invalid_frame ? buffer_size :
1910  (get_bits_count(&ctx->gb) + 7) >> 3;
1911 
1912  return bytes_read;
1913 }
1914 
1915 
1916 /** Uninitialize the ALS decoder.
1917  */
1919 {
1920  ALSDecContext *ctx = avctx->priv_data;
1921  int i;
1922 
1923  av_freep(&ctx->sconf.chan_pos);
1924 
1925  ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1926 
1927  av_freep(&ctx->const_block);
1928  av_freep(&ctx->shift_lsbs);
1929  av_freep(&ctx->opt_order);
1931  av_freep(&ctx->use_ltp);
1932  av_freep(&ctx->ltp_lag);
1933  av_freep(&ctx->ltp_gain);
1934  av_freep(&ctx->ltp_gain_buffer);
1935  av_freep(&ctx->quant_cof);
1936  av_freep(&ctx->lpc_cof);
1937  av_freep(&ctx->quant_cof_buffer);
1938  av_freep(&ctx->lpc_cof_buffer);
1940  av_freep(&ctx->prev_raw_samples);
1941  av_freep(&ctx->raw_samples);
1942  av_freep(&ctx->raw_buffer);
1943  av_freep(&ctx->chan_data);
1944  av_freep(&ctx->chan_data_buffer);
1945  av_freep(&ctx->reverted_channels);
1946  av_freep(&ctx->crc_buffer);
1947  if (ctx->mlz) {
1948  av_freep(&ctx->mlz->dict);
1949  av_freep(&ctx->mlz);
1950  }
1951  av_freep(&ctx->acf);
1952  av_freep(&ctx->last_acf_mantissa);
1953  av_freep(&ctx->shift_value);
1954  av_freep(&ctx->last_shift_value);
1955  if (ctx->raw_mantissa) {
1956  for (i = 0; i < avctx->channels; i++) {
1957  av_freep(&ctx->raw_mantissa[i]);
1958  }
1959  av_freep(&ctx->raw_mantissa);
1960  }
1961  av_freep(&ctx->larray);
1962  av_freep(&ctx->nbits);
1963 
1964  return 0;
1965 }
1966 
1967 
1968 /** Initialize the ALS decoder.
1969  */
1971 {
1972  unsigned int c;
1973  unsigned int channel_size;
1974  int num_buffers, ret;
1975  ALSDecContext *ctx = avctx->priv_data;
1976  ALSSpecificConfig *sconf = &ctx->sconf;
1977  ctx->avctx = avctx;
1978 
1979  if (!avctx->extradata) {
1980  av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1981  return AVERROR_INVALIDDATA;
1982  }
1983 
1984  if ((ret = read_specific_config(ctx)) < 0) {
1985  av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1986  goto fail;
1987  }
1988 
1989  if ((ret = check_specific_config(ctx)) < 0) {
1990  goto fail;
1991  }
1992 
1993  if (sconf->bgmc) {
1994  ret = ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1995  if (ret < 0)
1996  goto fail;
1997  }
1998  if (sconf->floating) {
1999  avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
2000  avctx->bits_per_raw_sample = 32;
2001  } else {
2002  avctx->sample_fmt = sconf->resolution > 1
2004  avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
2005  if (avctx->bits_per_raw_sample > 32) {
2006  av_log(avctx, AV_LOG_ERROR, "Bits per raw sample %d larger than 32.\n",
2007  avctx->bits_per_raw_sample);
2008  ret = AVERROR_INVALIDDATA;
2009  goto fail;
2010  }
2011  }
2012 
2013  // set maximum Rice parameter for progressive decoding based on resolution
2014  // This is not specified in 14496-3 but actually done by the reference
2015  // codec RM22 revision 2.
2016  ctx->s_max = sconf->resolution > 1 ? 31 : 15;
2017 
2018  // set lag value for long-term prediction
2019  ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
2020  (avctx->sample_rate >= 192000);
2021 
2022  // allocate quantized parcor coefficient buffer
2023  num_buffers = sconf->mc_coding ? avctx->channels : 1;
2024  if (num_buffers * (uint64_t)num_buffers > INT_MAX) // protect chan_data_buffer allocation
2025  return AVERROR_INVALIDDATA;
2026 
2027  ctx->quant_cof = av_malloc_array(num_buffers, sizeof(*ctx->quant_cof));
2028  ctx->lpc_cof = av_malloc_array(num_buffers, sizeof(*ctx->lpc_cof));
2029  ctx->quant_cof_buffer = av_malloc_array(num_buffers * sconf->max_order,
2030  sizeof(*ctx->quant_cof_buffer));
2031  ctx->lpc_cof_buffer = av_malloc_array(num_buffers * sconf->max_order,
2032  sizeof(*ctx->lpc_cof_buffer));
2034  sizeof(*ctx->lpc_cof_buffer));
2035 
2036  if (!ctx->quant_cof || !ctx->lpc_cof ||
2037  !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
2038  !ctx->lpc_cof_reversed_buffer) {
2039  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2040  ret = AVERROR(ENOMEM);
2041  goto fail;
2042  }
2043 
2044  // assign quantized parcor coefficient buffers
2045  for (c = 0; c < num_buffers; c++) {
2046  ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
2047  ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
2048  }
2049 
2050  // allocate and assign lag and gain data buffer for ltp mode
2051  ctx->const_block = av_malloc_array(num_buffers, sizeof(*ctx->const_block));
2052  ctx->shift_lsbs = av_malloc_array(num_buffers, sizeof(*ctx->shift_lsbs));
2053  ctx->opt_order = av_malloc_array(num_buffers, sizeof(*ctx->opt_order));
2054  ctx->store_prev_samples = av_malloc_array(num_buffers, sizeof(*ctx->store_prev_samples));
2055  ctx->use_ltp = av_mallocz_array(num_buffers, sizeof(*ctx->use_ltp));
2056  ctx->ltp_lag = av_malloc_array(num_buffers, sizeof(*ctx->ltp_lag));
2057  ctx->ltp_gain = av_malloc_array(num_buffers, sizeof(*ctx->ltp_gain));
2058  ctx->ltp_gain_buffer = av_malloc_array(num_buffers * 5, sizeof(*ctx->ltp_gain_buffer));
2059 
2060  if (!ctx->const_block || !ctx->shift_lsbs ||
2061  !ctx->opt_order || !ctx->store_prev_samples ||
2062  !ctx->use_ltp || !ctx->ltp_lag ||
2063  !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
2064  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2065  ret = AVERROR(ENOMEM);
2066  goto fail;
2067  }
2068 
2069  for (c = 0; c < num_buffers; c++)
2070  ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
2071 
2072  // allocate and assign channel data buffer for mcc mode
2073  if (sconf->mc_coding) {
2074  ctx->chan_data_buffer = av_mallocz_array(num_buffers * num_buffers,
2075  sizeof(*ctx->chan_data_buffer));
2076  ctx->chan_data = av_mallocz_array(num_buffers,
2077  sizeof(*ctx->chan_data));
2078  ctx->reverted_channels = av_malloc_array(num_buffers,
2079  sizeof(*ctx->reverted_channels));
2080 
2081  if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
2082  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2083  ret = AVERROR(ENOMEM);
2084  goto fail;
2085  }
2086 
2087  for (c = 0; c < num_buffers; c++)
2088  ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
2089  } else {
2090  ctx->chan_data = NULL;
2091  ctx->chan_data_buffer = NULL;
2092  ctx->reverted_channels = NULL;
2093  }
2094 
2095  channel_size = sconf->frame_length + sconf->max_order;
2096 
2097  ctx->prev_raw_samples = av_malloc_array(sconf->max_order, sizeof(*ctx->prev_raw_samples));
2098  ctx->raw_buffer = av_mallocz_array(avctx->channels * channel_size, sizeof(*ctx->raw_buffer));
2099  ctx->raw_samples = av_malloc_array(avctx->channels, sizeof(*ctx->raw_samples));
2100 
2101  if (sconf->floating) {
2102  ctx->acf = av_malloc_array(avctx->channels, sizeof(*ctx->acf));
2103  ctx->shift_value = av_malloc_array(avctx->channels, sizeof(*ctx->shift_value));
2104  ctx->last_shift_value = av_malloc_array(avctx->channels, sizeof(*ctx->last_shift_value));
2105  ctx->last_acf_mantissa = av_malloc_array(avctx->channels, sizeof(*ctx->last_acf_mantissa));
2106  ctx->raw_mantissa = av_mallocz_array(avctx->channels, sizeof(*ctx->raw_mantissa));
2107 
2108  ctx->larray = av_malloc_array(ctx->cur_frame_length * 4, sizeof(*ctx->larray));
2109  ctx->nbits = av_malloc_array(ctx->cur_frame_length, sizeof(*ctx->nbits));
2110  ctx->mlz = av_mallocz(sizeof(*ctx->mlz));
2111 
2112  if (!ctx->mlz || !ctx->acf || !ctx->shift_value || !ctx->last_shift_value
2113  || !ctx->last_acf_mantissa || !ctx->raw_mantissa) {
2114  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2115  ret = AVERROR(ENOMEM);
2116  goto fail;
2117  }
2118 
2119  ff_mlz_init_dict(avctx, ctx->mlz);
2120  ff_mlz_flush_dict(ctx->mlz);
2121 
2122  for (c = 0; c < avctx->channels; ++c) {
2123  ctx->raw_mantissa[c] = av_mallocz_array(ctx->cur_frame_length, sizeof(**ctx->raw_mantissa));
2124  }
2125  }
2126 
2127  // allocate previous raw sample buffer
2128  if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
2129  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2130  ret = AVERROR(ENOMEM);
2131  goto fail;
2132  }
2133 
2134  // assign raw samples buffers
2135  ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
2136  for (c = 1; c < avctx->channels; c++)
2137  ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
2138 
2139  // allocate crc buffer
2140  if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
2143  avctx->channels *
2145  sizeof(*ctx->crc_buffer));
2146  if (!ctx->crc_buffer) {
2147  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
2148  ret = AVERROR(ENOMEM);
2149  goto fail;
2150  }
2151  }
2152 
2153  ff_bswapdsp_init(&ctx->bdsp);
2154 
2155  return 0;
2156 
2157 fail:
2158  return ret;
2159 }
2160 
2161 
2162 /** Flush (reset) the frame ID after seeking.
2163  */
2164 static av_cold void flush(AVCodecContext *avctx)
2165 {
2166  ALSDecContext *ctx = avctx->priv_data;
2167 
2168  ctx->frame_id = 0;
2169 }
2170 
2171 
2173  .name = "als",
2174  .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),
2175  .type = AVMEDIA_TYPE_AUDIO,
2176  .id = AV_CODEC_ID_MP4ALS,
2177  .priv_data_size = sizeof(ALSDecContext),
2178  .init = decode_init,
2179  .close = decode_end,
2180  .decode = decode_frame,
2181  .flush = flush,
2182  .capabilities = AV_CODEC_CAP_SUBFRAMES | AV_CODEC_CAP_DR1,
2183  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
2184 };
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: internal.h:48
#define MUL64(a, b)
Definition: mathops.h:54
#define FF_SANE_NB_CHANNELS
Definition: internal.h:97
AVCodec ff_als_decoder
Definition: alsdec.c:2172
static int als_weighting(GetBitContext *gb, int k, int off)
Definition: alsdec.c:1214
static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
Decode the block data for a non-constant block.
Definition: alsdec.c:903
int msb_first
1 = original CRC calculated on big-endian system, 0 = little-endian
Definition: alsdec.c:162
#define NULL
Definition: coverity.c:32
unsigned char * larray
buffer to store the output of masked lz decompression
Definition: alsdec.c:237
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
static int shift(int a, int b)
Definition: sonic.c:82
This structure describes decoded (raw) audio or video data.
Definition: frame.h:314
int * use_ltp
contains use_ltp flags for all channels
Definition: alsdec.c:215
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
av_cold void ff_bgmc_end(uint8_t **cf_lut, int **cf_lut_status)
Release the lookup table arrays.
Definition: bgmc.c:480
MLZ * mlz
masked lz decompression structure
Definition: alsdec.c:231
int32_t ** raw_samples
decoded raw samples for each channel
Definition: alsdec.c:228
uint8_t * crc_buffer
buffer of byte order corrected samples used for CRC check
Definition: alsdec.c:230
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
static const int16_t mcc_weightings[]
Inter-channel weighting factors for multi-channel correlation.
Definition: alsdec.c:121
static void skip_bits_long(GetBitContext *s, int n)
Skips the specified number of bits.
Definition: get_bits.h:291
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int acc
Definition: yuv2rgb.c:555
#define avpriv_request_sample(...)
int block_switching
number of block switching levels
Definition: alsdec.c:170
int rlslms
use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
Definition: alsdec.c:177
int size
Definition: packet.h:364
static int check_specific_config(ALSDecContext *ctx)
Check the ALSSpecificConfig for unsupported features.
Definition: alsdec.c:446
#define av_bswap16
Definition: bswap.h:31
int av_log2(unsigned v)
Definition: intmath.c:26
int adapt_order
adaptive order: 1 = on, 0 = off
Definition: alsdec.c:166
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:36
static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
Read the frame data.
Definition: alsdec.c:1625
int32_t * lpc_cof_reversed_buffer
temporary buffer to set up a reversed versio of lpc_cof_buffer
Definition: alsdec.c:223
GetBitContext gb
Definition: alsdec.c:197
Block Gilbert-Moore decoder header.
int * nbits
contains the number of bits to read for masked lz decompression for all samples
Definition: alsdec.c:238
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:237
const char * master
Definition: vf_curves.c:117
unsigned int js_switch
if true, joint-stereo decoding is enforced
Definition: alsdec.c:204
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1762
static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
Read and decode block data successively.
Definition: alsdec.c:1061
static void error(const char *err)
#define INTERLEAVE_OUTPUT(bps)
#define sample
AVCodec.
Definition: codec.h:190
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
static int32_t decode_rice(GetBitContext *gb, unsigned int k)
Read and decode a Rice codeword.
Definition: alsdec.c:493
static int get_sbits_long(GetBitContext *s, int n)
Read 0-32 bits as a signed integer.
Definition: get_bits.h:590
uint8_t base
Definition: vp3data.h:202
int * ltp_lag
contains ltp lag values for all channels
Definition: alsdec.c:216
int * const_block
contains const_block flags for all channels
Definition: alsdec.c:211
static const uint8_t ltp_gain_values[4][4]
Gain values of p(0) for long-term prediction.
Definition: alsdec.c:110
static const SoftFloat FLOAT_0
0.0
Definition: softfloat.h:39
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
static av_cold int decode_init(AVCodecContext *avctx)
Initialize the ALS decoder.
Definition: alsdec.c:1970
BswapDSPContext bdsp
Definition: alsdec.c:198
int32_t * lpc_cof
coefficients of the direct form prediction
Definition: alsdec.c:255
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1199
uint8_t
#define av_cold
Definition: attributes.h:88
int avpriv_mpeg4audio_get_config2(MPEG4AudioConfig *c, const uint8_t *buf, int size, int sync_extension, void *logctx)
Parse MPEG-4 systems extradata from a raw buffer to retrieve audio configuration. ...
Definition: mpeg4audio.c:190
static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
Decode the block data for a constant block.
Definition: alsdec.c:614
float delta
void(* bswap_buf)(uint32_t *dst, const uint32_t *src, int w)
Definition: bswapdsp.h:25
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:92
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
int ** ltp_gain
gain values for ltp 5-tap filter for a channel
Definition: alsdec.c:217
static SoftFloat_IEEE754 av_bits2sf_ieee754(uint32_t n)
Make a softfloat out of the bitstream.
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:108
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:632
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:91
int chan_sort
channel rearrangement: 1 = on, 0 = off
Definition: alsdec.c:176
int joint_stereo
joint stereo: 1 = on, 0 = off
Definition: alsdec.c:173
Public header for CRC hash function implementation.
static SoftFloat_IEEE754 av_int2sf_ieee754(int64_t n, int e)
Convert integer to softfloat.
uint8_t * data
Definition: packet.h:363
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:219
#define ff_dlog(a,...)
bitstream reader API header.
static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame, unsigned int c, const unsigned int *div_blocks, unsigned int *js_blocks)
Decode blocks independently.
Definition: alsdec.c:1090
unsigned int block_length
number of samples within the block
Definition: alsdec.c:244
static void zero_remaining(unsigned int b, unsigned int b_max, const unsigned int *div_blocks, int32_t *buf)
Compute the number of samples left to decode for the current frame and sets these samples to zero...
Definition: alsdec.c:1075
#define max(a, b)
Definition: cuda_runtime.h:33
int ra_distance
distance between RA frames (in frames, 0...255)
Definition: alsdec.c:164
int weighting[6]
Definition: alsdec.c:190
channels
Definition: aptx.h:33
int32_t * quant_cof_buffer
contains all quantized parcor coefficients
Definition: alsdec.c:220
signed 32 bits
Definition: samplefmt.h:62
ALSChannelData * chan_data_buffer
contains channel data for all channels
Definition: alsdec.c:225
#define av_log(a,...)
int bgmc
"Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
Definition: alsdec.c:171
#define U(x)
Definition: vp56_arith.h:37
#define src
Definition: vp8dsp.c:254
MLZDict * dict
Definition: mlz.h:54
unsigned int cs_switch
if true, channel rearrangement is done
Definition: alsdec.c:205
static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:849
int * use_ltp
if true, long-term prediction is used
Definition: alsdec.c:251
enum RA_Flag ra_flag
indicates where the size of ra units is stored
Definition: alsdec.c:165
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
int ltp_lag_length
number of bits used for ltp lag value
Definition: alsdec.c:210
#define PTRDIFF_SPECIFIER
Definition: internal.h:228
static av_cold void dprint_specific_config(ALSDecContext *ctx)
Definition: alsdec.c:262
unsigned int * opt_order
prediction order of this block
Definition: alsdec.c:249
int * chan_pos
original channel positions
Definition: alsdec.c:179
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:153
AVCodecContext * avctx
Definition: alsdec.c:195
static const int16_t parcor_scaled_values[]
Scaled PARCOR values used for the first two PARCOR coefficients.
Definition: alsdec.c:71
static const SoftFloat FLOAT_1
1.0
Definition: softfloat.h:41
const char * r
Definition: vf_curves.c:114
static SoftFloat_IEEE754 multiply(SoftFloat_IEEE754 a, SoftFloat_IEEE754 b)
multiply two softfloats and handle the rounding off
Definition: alsdec.c:1383
int32_t ** lpc_cof
coefficients of the direct form prediction filter for a channel
Definition: alsdec.c:221
static int read_diff_float_data(ALSDecContext *ctx, unsigned int ra_frame)
Read and decode the floating point sample data.
Definition: alsdec.c:1442
int chan_config_info
mapping of channels to loudspeaker locations. Unused until setting channel configuration is implement...
Definition: alsdec.c:178
unsigned int num_blocks
number of blocks used in the current frame
Definition: alsdec.c:206
const char * name
Name of the codec implementation.
Definition: codec.h:197
int32_t * prev_raw_samples
contains unshifted raw samples from the previous block
Definition: alsdec.c:227
static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame, unsigned int c, const unsigned int *div_blocks, unsigned int *js_blocks)
Decode blocks dependently.
Definition: alsdec.c:1130
void ff_bgmc_decode_end(GetBitContext *gb)
Finish decoding.
Definition: bgmc.c:503
const AVCRC * crc_table
Definition: alsdec.c:199
GLsizei count
Definition: opengl_enc.c:108
#define FFMAX(a, b)
Definition: common.h:94
int * bgmc_lut_status
pointer at lookup table status flags used for BGMC
Definition: alsdec.c:209
#define fail()
Definition: checkasm.h:123
ALSSpecificConfig sconf
Definition: alsdec.c:196
int * store_prev_samples
if true, carryover samples have to be stored
Definition: alsdec.c:250
unsigned int * shift_lsbs
contains shift_lsbs flags for all channels
Definition: alsdec.c:212
#define b
Definition: input.c:41
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:1660
#define FFMIN(a, b)
Definition: common.h:96
static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
Read the block data for a non-constant block.
Definition: alsdec.c:628
int ff_mlz_decompression(MLZ *mlz, GetBitContext *gb, int size, unsigned char *buff)
Run mlz decompression on the next size bits and the output will be stored in buff.
Definition: mlz.c:123
int chan_config
indicates that a chan_config_info field is present
Definition: alsdec.c:175
int32_t
AVFormatContext * ctx
Definition: movenc.c:48
#define EXP_BIAS
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length)
Calculate the CRC of a block.
Definition: crc.c:392
int * last_shift_value
contains last shift value for all channels
Definition: alsdec.c:235
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
static int av_cmp_sf_ieee754(SoftFloat_IEEE754 a, SoftFloat_IEEE754 b)
Compare a with b strictly.
#define s(width, name)
Definition: cbs_vp9.c:257
void ff_bgmc_decode(GetBitContext *gb, unsigned int num, int32_t *dst, int delta, unsigned int sx, unsigned int *h, unsigned int *l, unsigned int *v, uint8_t *cf_lut, int *cf_lut_status)
Read and decode a block Gilbert-Moore coded symbol.
Definition: bgmc.c:510
static av_cold int decode_end(AVCodecContext *avctx)
Uninitialize the ALS decoder.
Definition: alsdec.c:1918
int * const_block
if true, this is a constant value block
Definition: alsdec.c:246
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:1671
int floating
1 = IEEE 32-bit floating-point, 0 = integer
Definition: alsdec.c:161
int time_diff_flag
Definition: alsdec.c:187
SoftFloat_IEEE754 * acf
contains common multiplier for all channels
Definition: alsdec.c:232
int master_channel
Definition: alsdec.c:186
uint32_t crc
CRC value calculated from decoded data.
Definition: alsdec.c:201
int coef_table
table index of Rice code parameters
Definition: alsdec.c:167
static int read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
Read the block data for a constant block.
Definition: alsdec.c:584
#define FF_ARRAY_ELEMS(a)
int sb_part
sub-block partition
Definition: alsdec.c:172
MLZ data strucure.
Definition: mlz.h:47
int32_t * raw_other
decoded raw samples of the other channel of a channel pair
Definition: alsdec.c:258
if(ret)
uint8_t * bgmc_lut
pointer at lookup tables used for BGMC
Definition: alsdec.c:208
av_cold void ff_mlz_init_dict(void *context, MLZ *mlz)
Initialize the dictionary.
Definition: mlz.c:23
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
int * ltp_gain
gain values for ltp 5-tap filter
Definition: alsdec.c:253
int js_blocks
true if this block contains a difference signal
Definition: alsdec.c:247
#define av_bswap32
Definition: bswap.h:33
unsigned int ra_block
if true, this is a random access block
Definition: alsdec.c:245
Libavcodec external API header.
static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
Convert PARCOR coefficient k to direct filter coefficient.
Definition: alsdec.c:511
int * shift_value
value by which the binary point is to be shifted for all channels
Definition: alsdec.c:234
int sample_rate
samples per second
Definition: avcodec.h:1191
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:677
#define abs(x)
Definition: cuda_runtime.h:35
main external API structure.
Definition: avcodec.h:531
ALSChannelData ** chan_data
channel data for multi-channel correlation
Definition: alsdec.c:224
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Decode an ALS frame.
Definition: alsdec.c:1782
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1879
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2]...the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so...,+,-,+,-,+,+,-,+,-,+,...hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32-hcoeff[1]-hcoeff[2]-...a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2}an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||.........intra?||||:Block01:yes no||||:Block02:.................||||:Block03::y DC::ref index:||||:Block04::cb DC::motion x:||||.........:cr DC::motion y:||||.................|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------------------------------|||Y subbands||Cb subbands||Cr subbands||||------||------||------|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||------||------||------||||------||------||------|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||------||------||------||||------||------||------|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||------||------||------||||------||------||------|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------------------------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction------------|\Dequantization-------------------\||Reference frames|\IDWT|--------------|Motion\|||Frame 0||Frame 1||Compensation.OBMC v-------|--------------|--------------.\------> Frame n output Frame Frame<----------------------------------/|...|-------------------Range Coder:============Binary Range Coder:-------------------The implemented range coder is an adapted version based upon"Range encoding: an algorithm for removing redundancy from a digitised message."by G.N.N.Martin.The symbols encoded by the Snow range coder are bits(0|1).The associated probabilities are not fix but change depending on the symbol mix seen so far.bit seen|new state---------+-----------------------------------------------0|256-state_transition_table[256-old_state];1|state_transition_table[old_state];state_transition_table={0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:-------------------------FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1.the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled left
Definition: snow.txt:206
#define MISSING_ERR(cond, str, errval)
int extradata_size
Definition: avcodec.h:633
#define AV_EF_CAREFUL
consider things that violate the spec, are fast to calculate and have not been seen in the wild as er...
Definition: avcodec.h:1674
int highest_decoded_channel
Definition: alsdec.c:239
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:498
static void skip_bits1(GetBitContext *s)
Definition: get_bits.h:538
unsigned int s_max
maximum Rice parameter allowed in entropy coding
Definition: alsdec.c:207
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:467
#define AV_CODEC_CAP_SUBFRAMES
Codec can output multiple frames per AVPacket Normally demuxers return one frame at a time...
Definition: codec.h:93
int * ltp_lag
lag value for long-term prediction
Definition: alsdec.c:252
int32_t * lpc_cof_buffer
contains all coefficients of the direct form prediction filter
Definition: alsdec.c:222
#define AV_EF_CRCCHECK
Verify checksums embedded in the bitstream (could be of either encoded or decoded data...
Definition: avcodec.h:1668
static const int8_t parcor_rice_table[3][20][2]
Rice parameters and corresponding index offsets for decoding the indices of scaled PARCOR values...
Definition: alsdec.c:50
RA_Flag
Definition: alsdec.c:151
static av_cold int read_specific_config(ALSDecContext *ctx)
Read an ALSSpecificConfig from a buffer into the output struct.
Definition: alsdec.c:292
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:546
int long_term_prediction
long term prediction (LTP): 1 = on, 0 = off
Definition: alsdec.c:168
int32_t * raw_samples
decoded raw samples / residuals for this block
Definition: alsdec.c:256
int * reverted_channels
stores a flag for each reverted channel
Definition: alsdec.c:226
int ff_bgmc_decode_init(GetBitContext *gb, unsigned int *h, unsigned int *l, unsigned int *v)
Initialize decoding and reads the first value.
Definition: bgmc.c:488
int * last_acf_mantissa
contains the last acf mantissa data of common multiplier for all channels
Definition: alsdec.c:233
unsigned int * opt_order
contains opt_order flags for all channels
Definition: alsdec.c:213
int32_t * raw_buffer
contains all decoded raw samples including carryover samples
Definition: alsdec.c:229
int max_order
maximum prediction order (0..1023)
Definition: alsdec.c:169
uint32_t samples
number of samples, 0xFFFFFFFF if unknown
Definition: alsdec.c:159
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:328
int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt)
Return number of bytes per sample.
Definition: samplefmt.c:106
const AVCRC * av_crc_get_table(AVCRCId crc_id)
Get an initialized standard CRC table.
Definition: crc.c:374
int mc_coding
extended inter-channel coding (multi channel coding): 1 = on, 0 = off
Definition: alsdec.c:174
int
static const uint8_t tail_code[16][6]
Tail codes used in arithmetic coding using block Gilbert-Moore codes.
Definition: alsdec.c:131
common internal api header.
int32_t * prev_raw_samples
contains unshifted raw samples from the previous block
Definition: alsdec.c:257
static int get_unary(GetBitContext *gb, int stop, int len)
Get unary code of limited length.
Definition: unary.h:46
av_cold void ff_mlz_flush_dict(MLZ *mlz)
Flush the dictionary.
Definition: mlz.c:35
static av_cold void flush(AVCodecContext *avctx)
Flush (reset) the frame ID after seeking.
Definition: alsdec.c:2164
signed 16 bits
Definition: samplefmt.h:61
int time_diff_index
Definition: alsdec.c:189
int * ltp_gain_buffer
contains all gain values for ltp 5-tap filter
Definition: alsdec.c:218
int32_t * quant_cof
quantized parcor coefficients
Definition: alsdec.c:254
#define MKBETAG(a, b, c, d)
Definition: common.h:406
static void parse_bs_info(const uint32_t bs_info, unsigned int n, unsigned int div, unsigned int **div_blocks, unsigned int *num_blocks)
Parse the bs_info field to extract the block partitioning used in block switching mode...
Definition: alsdec.c:470
av_cold void ff_bswapdsp_init(BswapDSPContext *c)
Definition: bswapdsp.c:49
void * priv_data
Definition: avcodec.h:558
int32_t ** quant_cof
quantized parcor coefficients for a channel
Definition: alsdec.c:219
int channels
number of audio channels
Definition: avcodec.h:1192
int crc_enabled
enable Cyclic Redundancy Checksum
Definition: alsdec.c:180
int ** raw_mantissa
decoded mantissa bits of the difference signal
Definition: alsdec.c:236
uint32_t crc_org
CRC value of the original input data.
Definition: alsdec.c:200
static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
Decode the block data.
Definition: alsdec.c:1035
static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
Read the block data.
Definition: alsdec.c:1012
int frame_length
frame length for each frame (last frame may differ)
Definition: alsdec.c:163
static const uint8_t * align_get_bits(GetBitContext *s)
Definition: get_bits.h:693
int stop_flag
Definition: alsdec.c:185
static const struct twinvq_data tab
unsigned int * shift_lsbs
shift of values for this block
Definition: alsdec.c:248
#define av_freep(p)
av_cold int ff_bgmc_init(AVCodecContext *avctx, uint8_t **cf_lut, int **cf_lut_status)
Initialize the lookup table arrays.
Definition: bgmc.c:460
#define av_malloc_array(a, b)
static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
Read the channel data.
Definition: alsdec.c:1223
static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks, uint32_t *bs_info)
Read block switching field if necessary and set actual block sizes.
Definition: alsdec.c:531
int * store_prev_samples
contains store_prev_samples flags for all channels
Definition: alsdec.c:214
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
static SoftFloat_IEEE754 av_div_sf_ieee754(SoftFloat_IEEE754 a, SoftFloat_IEEE754 b)
Divide a by b.
unsigned int frame_id
the frame ID / number of the current frame
Definition: alsdec.c:203
static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd, ALSChannelData **cd, int *reverted, unsigned int offset, int c)
Recursively reverts the inter-channel correlation for a block.
Definition: alsdec.c:1270
static double val(void *priv, double ch)
Definition: aeval.c:76
This structure stores compressed data.
Definition: packet.h:340
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:380
uint32_t AVCRC
Definition: crc.h:47
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:50
for(j=16;j >0;--j)
unsigned int cur_frame_length
length of the current frame to decode
Definition: alsdec.c:202
int i
Definition: input.c:407
static av_always_inline int get_bitsz(GetBitContext *s, int n)
Read 0-25 bits.
Definition: get_bits.h:415
GLuint buffer
Definition: opengl_enc.c:101
int resolution
000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
Definition: alsdec.c:160
void * av_mallocz_array(size_t nmemb, size_t size)
Definition: mem.c:190
int time_diff_sign
Definition: alsdec.c:188