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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 "bytestream.h"
35 #include "bgmc.h"
36 #include "bswapdsp.h"
37 #include "internal.h"
38 #include "libavutil/samplefmt.h"
39 #include "libavutil/crc.h"
40 
41 #include <stdint.h>
42 
43 /** Rice parameters and corresponding index offsets for decoding the
44  * indices of scaled PARCOR values. The table chosen is set globally
45  * by the encoder and stored in ALSSpecificConfig.
46  */
47 static const int8_t parcor_rice_table[3][20][2] = {
48  { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
49  { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
50  { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
51  { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
52  { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
53  { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
54  {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
55  { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
56  { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
57  { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
58  {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
59  { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
60 };
61 
62 
63 /** Scaled PARCOR values used for the first two PARCOR coefficients.
64  * To be indexed by the Rice coded indices.
65  * Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20)
66  * Actual values are divided by 32 in order to be stored in 16 bits.
67  */
68 static const int16_t parcor_scaled_values[] = {
69  -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
70  -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
71  -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
72  -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
73  -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
74  -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
75  -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
76  -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
77  -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
78  -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
79  -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
80  -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
81  -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
82  -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
83  -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
84  -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
85  -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
86  -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
87  -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
88  -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
89  -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
90  -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
91  -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
92  46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
93  143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
94  244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
95  349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
96  458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
97  571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
98  688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
99  810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
100  935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
101 };
102 
103 
104 /** Gain values of p(0) for long-term prediction.
105  * To be indexed by the Rice coded indices.
106  */
107 static const uint8_t ltp_gain_values [4][4] = {
108  { 0, 8, 16, 24},
109  {32, 40, 48, 56},
110  {64, 70, 76, 82},
111  {88, 92, 96, 100}
112 };
113 
114 
115 /** Inter-channel weighting factors for multi-channel correlation.
116  * To be indexed by the Rice coded indices.
117  */
118 static const int16_t mcc_weightings[] = {
119  204, 192, 179, 166, 153, 140, 128, 115,
120  102, 89, 76, 64, 51, 38, 25, 12,
121  0, -12, -25, -38, -51, -64, -76, -89,
122  -102, -115, -128, -140, -153, -166, -179, -192
123 };
124 
125 
126 /** Tail codes used in arithmetic coding using block Gilbert-Moore codes.
127  */
128 static const uint8_t tail_code[16][6] = {
129  { 74, 44, 25, 13, 7, 3},
130  { 68, 42, 24, 13, 7, 3},
131  { 58, 39, 23, 13, 7, 3},
132  {126, 70, 37, 19, 10, 5},
133  {132, 70, 37, 20, 10, 5},
134  {124, 70, 38, 20, 10, 5},
135  {120, 69, 37, 20, 11, 5},
136  {116, 67, 37, 20, 11, 5},
137  {108, 66, 36, 20, 10, 5},
138  {102, 62, 36, 20, 10, 5},
139  { 88, 58, 34, 19, 10, 5},
140  {162, 89, 49, 25, 13, 7},
141  {156, 87, 49, 26, 14, 7},
142  {150, 86, 47, 26, 14, 7},
143  {142, 84, 47, 26, 14, 7},
144  {131, 79, 46, 26, 14, 7}
145 };
146 
147 
148 enum RA_Flag {
149  RA_FLAG_NONE,
150  RA_FLAG_FRAMES,
151  RA_FLAG_HEADER
152 };
153 
154 
155 typedef struct ALSSpecificConfig {
156  uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown
157  int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
158  int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer
159  int msb_first; ///< 1 = original CRC calculated on big-endian system, 0 = little-endian
160  int frame_length; ///< frame length for each frame (last frame may differ)
161  int ra_distance; ///< distance between RA frames (in frames, 0...255)
162  enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored
163  int adapt_order; ///< adaptive order: 1 = on, 0 = off
164  int coef_table; ///< table index of Rice code parameters
165  int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off
166  int max_order; ///< maximum prediction order (0..1023)
167  int block_switching; ///< number of block switching levels
168  int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
169  int sb_part; ///< sub-block partition
170  int joint_stereo; ///< joint stereo: 1 = on, 0 = off
171  int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off
172  int chan_config; ///< indicates that a chan_config_info field is present
173  int chan_sort; ///< channel rearrangement: 1 = on, 0 = off
174  int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
175  int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented.
176  int *chan_pos; ///< original channel positions
177  int crc_enabled; ///< enable Cyclic Redundancy Checksum
178 } ALSSpecificConfig;
179 
180 
181 typedef struct ALSChannelData {
182  int stop_flag;
183  int master_channel;
184  int time_diff_flag;
185  int time_diff_sign;
186  int time_diff_index;
187  int weighting[6];
188 } ALSChannelData;
189 
190 
191 typedef struct ALSDecContext {
192  AVCodecContext *avctx;
193  ALSSpecificConfig sconf;
194  GetBitContext gb;
195  BswapDSPContext bdsp;
196  const AVCRC *crc_table;
197  uint32_t crc_org; ///< CRC value of the original input data
198  uint32_t crc; ///< CRC value calculated from decoded data
199  unsigned int cur_frame_length; ///< length of the current frame to decode
200  unsigned int frame_id; ///< the frame ID / number of the current frame
201  unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
202  unsigned int cs_switch; ///< if true, channel rearrangement is done
203  unsigned int num_blocks; ///< number of blocks used in the current frame
204  unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding
205  uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
206  int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
207  int ltp_lag_length; ///< number of bits used for ltp lag value
208  int *const_block; ///< contains const_block flags for all channels
209  unsigned int *shift_lsbs; ///< contains shift_lsbs flags for all channels
210  unsigned int *opt_order; ///< contains opt_order flags for all channels
211  int *store_prev_samples; ///< contains store_prev_samples flags for all channels
212  int *use_ltp; ///< contains use_ltp flags for all channels
213  int *ltp_lag; ///< contains ltp lag values for all channels
214  int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
215  int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
216  int32_t **quant_cof; ///< quantized parcor coefficients for a channel
217  int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
218  int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
219  int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
220  int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
221  ALSChannelData **chan_data; ///< channel data for multi-channel correlation
222  ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
223  int *reverted_channels; ///< stores a flag for each reverted channel
224  int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
225  int32_t **raw_samples; ///< decoded raw samples for each channel
226  int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
227  uint8_t *crc_buffer; ///< buffer of byte order corrected samples used for CRC check
228 } ALSDecContext;
229 
230 
231 typedef struct ALSBlockData {
232  unsigned int block_length; ///< number of samples within the block
233  unsigned int ra_block; ///< if true, this is a random access block
234  int *const_block; ///< if true, this is a constant value block
235  int js_blocks; ///< true if this block contains a difference signal
236  unsigned int *shift_lsbs; ///< shift of values for this block
237  unsigned int *opt_order; ///< prediction order of this block
238  int *store_prev_samples;///< if true, carryover samples have to be stored
239  int *use_ltp; ///< if true, long-term prediction is used
240  int *ltp_lag; ///< lag value for long-term prediction
241  int *ltp_gain; ///< gain values for ltp 5-tap filter
242  int32_t *quant_cof; ///< quantized parcor coefficients
243  int32_t *lpc_cof; ///< coefficients of the direct form prediction
244  int32_t *raw_samples; ///< decoded raw samples / residuals for this block
245  int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
246  int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
247 } ALSBlockData;
248 
249 
250 static av_cold void dprint_specific_config(ALSDecContext *ctx)
251 {
252 #ifdef DEBUG
253  AVCodecContext *avctx = ctx->avctx;
254  ALSSpecificConfig *sconf = &ctx->sconf;
255 
256  ff_dlog(avctx, "resolution = %i\n", sconf->resolution);
257  ff_dlog(avctx, "floating = %i\n", sconf->floating);
258  ff_dlog(avctx, "frame_length = %i\n", sconf->frame_length);
259  ff_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance);
260  ff_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag);
261  ff_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order);
262  ff_dlog(avctx, "coef_table = %i\n", sconf->coef_table);
263  ff_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
264  ff_dlog(avctx, "max_order = %i\n", sconf->max_order);
265  ff_dlog(avctx, "block_switching = %i\n", sconf->block_switching);
266  ff_dlog(avctx, "bgmc = %i\n", sconf->bgmc);
267  ff_dlog(avctx, "sb_part = %i\n", sconf->sb_part);
268  ff_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
269  ff_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding);
270  ff_dlog(avctx, "chan_config = %i\n", sconf->chan_config);
271  ff_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort);
272  ff_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms);
273  ff_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
274 #endif
275 }
276 
277 
278 /** Read an ALSSpecificConfig from a buffer into the output struct.
279  */
280 static av_cold int read_specific_config(ALSDecContext *ctx)
281 {
282  GetBitContext gb;
283  uint64_t ht_size;
284  int i, config_offset;
285  MPEG4AudioConfig m4ac = {0};
286  ALSSpecificConfig *sconf = &ctx->sconf;
287  AVCodecContext *avctx = ctx->avctx;
288  uint32_t als_id, header_size, trailer_size;
289  int ret;
290 
291  if ((ret = init_get_bits8(&gb, avctx->extradata, avctx->extradata_size)) < 0)
292  return ret;
293 
294  config_offset = avpriv_mpeg4audio_get_config(&m4ac, avctx->extradata,
295  avctx->extradata_size * 8, 1);
296 
297  if (config_offset < 0)
298  return AVERROR_INVALIDDATA;
299 
300  skip_bits_long(&gb, config_offset);
301 
302  if (get_bits_left(&gb) < (30 << 3))
303  return AVERROR_INVALIDDATA;
304 
305  // read the fixed items
306  als_id = get_bits_long(&gb, 32);
307  avctx->sample_rate = m4ac.sample_rate;
308  skip_bits_long(&gb, 32); // sample rate already known
309  sconf->samples = get_bits_long(&gb, 32);
310  avctx->channels = m4ac.channels;
311  skip_bits(&gb, 16); // number of channels already known
312  skip_bits(&gb, 3); // skip file_type
313  sconf->resolution = get_bits(&gb, 3);
314  sconf->floating = get_bits1(&gb);
315  sconf->msb_first = get_bits1(&gb);
316  sconf->frame_length = get_bits(&gb, 16) + 1;
317  sconf->ra_distance = get_bits(&gb, 8);
318  sconf->ra_flag = get_bits(&gb, 2);
319  sconf->adapt_order = get_bits1(&gb);
320  sconf->coef_table = get_bits(&gb, 2);
321  sconf->long_term_prediction = get_bits1(&gb);
322  sconf->max_order = get_bits(&gb, 10);
323  sconf->block_switching = get_bits(&gb, 2);
324  sconf->bgmc = get_bits1(&gb);
325  sconf->sb_part = get_bits1(&gb);
326  sconf->joint_stereo = get_bits1(&gb);
327  sconf->mc_coding = get_bits1(&gb);
328  sconf->chan_config = get_bits1(&gb);
329  sconf->chan_sort = get_bits1(&gb);
330  sconf->crc_enabled = get_bits1(&gb);
331  sconf->rlslms = get_bits1(&gb);
332  skip_bits(&gb, 5); // skip 5 reserved bits
333  skip_bits1(&gb); // skip aux_data_enabled
334 
335 
336  // check for ALSSpecificConfig struct
337  if (als_id != MKBETAG('A','L','S','\0'))
338  return AVERROR_INVALIDDATA;
339 
340  ctx->cur_frame_length = sconf->frame_length;
341 
342  // read channel config
343  if (sconf->chan_config)
344  sconf->chan_config_info = get_bits(&gb, 16);
345  // TODO: use this to set avctx->channel_layout
346 
347 
348  // read channel sorting
349  if (sconf->chan_sort && avctx->channels > 1) {
350  int chan_pos_bits = av_ceil_log2(avctx->channels);
351  int bits_needed = avctx->channels * chan_pos_bits + 7;
352  if (get_bits_left(&gb) < bits_needed)
353  return AVERROR_INVALIDDATA;
354 
355  if (!(sconf->chan_pos = av_malloc_array(avctx->channels, sizeof(*sconf->chan_pos))))
356  return AVERROR(ENOMEM);
357 
358  ctx->cs_switch = 1;
359 
360  for (i = 0; i < avctx->channels; i++) {
361  sconf->chan_pos[i] = -1;
362  }
363 
364  for (i = 0; i < avctx->channels; i++) {
365  int idx;
366 
367  idx = get_bits(&gb, chan_pos_bits);
368  if (idx >= avctx->channels || sconf->chan_pos[idx] != -1) {
369  av_log(avctx, AV_LOG_WARNING, "Invalid channel reordering.\n");
370  ctx->cs_switch = 0;
371  break;
372  }
373  sconf->chan_pos[idx] = i;
374  }
375 
376  align_get_bits(&gb);
377  }
378 
379 
380  // read fixed header and trailer sizes,
381  // if size = 0xFFFFFFFF then there is no data field!
382  if (get_bits_left(&gb) < 64)
383  return AVERROR_INVALIDDATA;
384 
385  header_size = get_bits_long(&gb, 32);
386  trailer_size = get_bits_long(&gb, 32);
387  if (header_size == 0xFFFFFFFF)
388  header_size = 0;
389  if (trailer_size == 0xFFFFFFFF)
390  trailer_size = 0;
391 
392  ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
393 
394 
395  // skip the header and trailer data
396  if (get_bits_left(&gb) < ht_size)
397  return AVERROR_INVALIDDATA;
398 
399  if (ht_size > INT32_MAX)
400  return AVERROR_PATCHWELCOME;
401 
402  skip_bits_long(&gb, ht_size);
403 
404 
405  // initialize CRC calculation
406  if (sconf->crc_enabled) {
407  if (get_bits_left(&gb) < 32)
408  return AVERROR_INVALIDDATA;
409 
410  if (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL)) {
411  ctx->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
412  ctx->crc = 0xFFFFFFFF;
413  ctx->crc_org = ~get_bits_long(&gb, 32);
414  } else
415  skip_bits_long(&gb, 32);
416  }
417 
418 
419  // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
420 
421  dprint_specific_config(ctx);
422 
423  return 0;
424 }
425 
426 
427 /** Check the ALSSpecificConfig for unsupported features.
428  */
429 static int check_specific_config(ALSDecContext *ctx)
430 {
431  ALSSpecificConfig *sconf = &ctx->sconf;
432  int error = 0;
433 
434  // report unsupported feature and set error value
435  #define MISSING_ERR(cond, str, errval) \
436  { \
437  if (cond) { \
438  avpriv_report_missing_feature(ctx->avctx, \
439  str); \
440  error = errval; \
441  } \
442  }
443 
444  MISSING_ERR(sconf->floating, "Floating point decoding", AVERROR_PATCHWELCOME);
445  MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME);
446 
447  return error;
448 }
449 
450 
451 /** Parse the bs_info field to extract the block partitioning used in
452  * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
453  */
454 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
455  unsigned int div, unsigned int **div_blocks,
456  unsigned int *num_blocks)
457 {
458  if (n < 31 && ((bs_info << n) & 0x40000000)) {
459  // if the level is valid and the investigated bit n is set
460  // then recursively check both children at bits (2n+1) and (2n+2)
461  n *= 2;
462  div += 1;
463  parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
464  parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
465  } else {
466  // else the bit is not set or the last level has been reached
467  // (bit implicitly not set)
468  **div_blocks = div;
469  (*div_blocks)++;
470  (*num_blocks)++;
471  }
472 }
473 
474 
475 /** Read and decode a Rice codeword.
476  */
477 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
478 {
479  int max = get_bits_left(gb) - k;
480  int q = get_unary(gb, 0, max);
481  int r = k ? get_bits1(gb) : !(q & 1);
482 
483  if (k > 1) {
484  q <<= (k - 1);
485  q += get_bits_long(gb, k - 1);
486  } else if (!k) {
487  q >>= 1;
488  }
489  return r ? q : ~q;
490 }
491 
492 
493 /** Convert PARCOR coefficient k to direct filter coefficient.
494  */
495 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
496 {
497  int i, j;
498 
499  for (i = 0, j = k - 1; i < j; i++, j--) {
500  int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
501  cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
502  cof[i] += tmp1;
503  }
504  if (i == j)
505  cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
506 
507  cof[k] = par[k];
508 }
509 
510 
511 /** Read block switching field if necessary and set actual block sizes.
512  * Also assure that the block sizes of the last frame correspond to the
513  * actual number of samples.
514  */
515 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
516  uint32_t *bs_info)
517 {
518  ALSSpecificConfig *sconf = &ctx->sconf;
519  GetBitContext *gb = &ctx->gb;
520  unsigned int *ptr_div_blocks = div_blocks;
521  unsigned int b;
522 
523  if (sconf->block_switching) {
524  unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
525  *bs_info = get_bits_long(gb, bs_info_len);
526  *bs_info <<= (32 - bs_info_len);
527  }
528 
529  ctx->num_blocks = 0;
530  parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
531 
532  // The last frame may have an overdetermined block structure given in
533  // the bitstream. In that case the defined block structure would need
534  // more samples than available to be consistent.
535  // The block structure is actually used but the block sizes are adapted
536  // to fit the actual number of available samples.
537  // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
538  // This results in the actual block sizes: 2 2 1 0.
539  // This is not specified in 14496-3 but actually done by the reference
540  // codec RM22 revision 2.
541  // This appears to happen in case of an odd number of samples in the last
542  // frame which is actually not allowed by the block length switching part
543  // of 14496-3.
544  // The ALS conformance files feature an odd number of samples in the last
545  // frame.
546 
547  for (b = 0; b < ctx->num_blocks; b++)
548  div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
549 
550  if (ctx->cur_frame_length != ctx->sconf.frame_length) {
551  unsigned int remaining = ctx->cur_frame_length;
552 
553  for (b = 0; b < ctx->num_blocks; b++) {
554  if (remaining <= div_blocks[b]) {
555  div_blocks[b] = remaining;
556  ctx->num_blocks = b + 1;
557  break;
558  }
559 
560  remaining -= div_blocks[b];
561  }
562  }
563 }
564 
565 
566 /** Read the block data for a constant block
567  */
568 static int read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
569 {
570  ALSSpecificConfig *sconf = &ctx->sconf;
571  AVCodecContext *avctx = ctx->avctx;
572  GetBitContext *gb = &ctx->gb;
573 
574  if (bd->block_length <= 0)
575  return AVERROR_INVALIDDATA;
576 
577  *bd->raw_samples = 0;
578  *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
579  bd->js_blocks = get_bits1(gb);
580 
581  // skip 5 reserved bits
582  skip_bits(gb, 5);
583 
584  if (*bd->const_block) {
585  unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
586  *bd->raw_samples = get_sbits_long(gb, const_val_bits);
587  }
588 
589  // ensure constant block decoding by reusing this field
590  *bd->const_block = 1;
591 
592  return 0;
593 }
594 
595 
596 /** Decode the block data for a constant block
597  */
598 static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
599 {
600  int smp = bd->block_length - 1;
601  int32_t val = *bd->raw_samples;
602  int32_t *dst = bd->raw_samples + 1;
603 
604  // write raw samples into buffer
605  for (; smp; smp--)
606  *dst++ = val;
607 }
608 
609 
610 /** Read the block data for a non-constant block
611  */
612 static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
613 {
614  ALSSpecificConfig *sconf = &ctx->sconf;
615  AVCodecContext *avctx = ctx->avctx;
616  GetBitContext *gb = &ctx->gb;
617  unsigned int k;
618  unsigned int s[8];
619  unsigned int sx[8];
620  unsigned int sub_blocks, log2_sub_blocks, sb_length;
621  unsigned int start = 0;
622  unsigned int opt_order;
623  int sb;
624  int32_t *quant_cof = bd->quant_cof;
625  int32_t *current_res;
626 
627 
628  // ensure variable block decoding by reusing this field
629  *bd->const_block = 0;
630 
631  *bd->opt_order = 1;
632  bd->js_blocks = get_bits1(gb);
633 
634  opt_order = *bd->opt_order;
635 
636  // determine the number of subblocks for entropy decoding
637  if (!sconf->bgmc && !sconf->sb_part) {
638  log2_sub_blocks = 0;
639  } else {
640  if (sconf->bgmc && sconf->sb_part)
641  log2_sub_blocks = get_bits(gb, 2);
642  else
643  log2_sub_blocks = 2 * get_bits1(gb);
644  }
645 
646  sub_blocks = 1 << log2_sub_blocks;
647 
648  // do not continue in case of a damaged stream since
649  // block_length must be evenly divisible by sub_blocks
650  if (bd->block_length & (sub_blocks - 1)) {
651  av_log(avctx, AV_LOG_WARNING,
652  "Block length is not evenly divisible by the number of subblocks.\n");
653  return AVERROR_INVALIDDATA;
654  }
655 
656  sb_length = bd->block_length >> log2_sub_blocks;
657 
658  if (sconf->bgmc) {
659  s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
660  for (k = 1; k < sub_blocks; k++)
661  s[k] = s[k - 1] + decode_rice(gb, 2);
662 
663  for (k = 0; k < sub_blocks; k++) {
664  sx[k] = s[k] & 0x0F;
665  s [k] >>= 4;
666  }
667  } else {
668  s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
669  for (k = 1; k < sub_blocks; k++)
670  s[k] = s[k - 1] + decode_rice(gb, 0);
671  }
672  for (k = 1; k < sub_blocks; k++)
673  if (s[k] > 32) {
674  av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n");
675  return AVERROR_INVALIDDATA;
676  }
677 
678  if (get_bits1(gb))
679  *bd->shift_lsbs = get_bits(gb, 4) + 1;
680 
681  *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
682 
683 
684  if (!sconf->rlslms) {
685  if (sconf->adapt_order && sconf->max_order) {
686  int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
687  2, sconf->max_order + 1));
688  *bd->opt_order = get_bits(gb, opt_order_length);
689  if (*bd->opt_order > sconf->max_order) {
690  *bd->opt_order = sconf->max_order;
691  av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n");
692  return AVERROR_INVALIDDATA;
693  }
694  } else {
695  *bd->opt_order = sconf->max_order;
696  }
697  if (*bd->opt_order > bd->block_length) {
698  *bd->opt_order = bd->block_length;
699  av_log(avctx, AV_LOG_ERROR, "Predictor order too large.\n");
700  return AVERROR_INVALIDDATA;
701  }
702  opt_order = *bd->opt_order;
703 
704  if (opt_order) {
705  int add_base;
706 
707  if (sconf->coef_table == 3) {
708  add_base = 0x7F;
709 
710  // read coefficient 0
711  quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
712 
713  // read coefficient 1
714  if (opt_order > 1)
715  quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
716 
717  // read coefficients 2 to opt_order
718  for (k = 2; k < opt_order; k++)
719  quant_cof[k] = get_bits(gb, 7);
720  } else {
721  int k_max;
722  add_base = 1;
723 
724  // read coefficient 0 to 19
725  k_max = FFMIN(opt_order, 20);
726  for (k = 0; k < k_max; k++) {
727  int rice_param = parcor_rice_table[sconf->coef_table][k][1];
728  int offset = parcor_rice_table[sconf->coef_table][k][0];
729  quant_cof[k] = decode_rice(gb, rice_param) + offset;
730  if (quant_cof[k] < -64 || quant_cof[k] > 63) {
731  av_log(avctx, AV_LOG_ERROR,
732  "quant_cof %"PRId32" is out of range.\n",
733  quant_cof[k]);
734  return AVERROR_INVALIDDATA;
735  }
736  }
737 
738  // read coefficients 20 to 126
739  k_max = FFMIN(opt_order, 127);
740  for (; k < k_max; k++)
741  quant_cof[k] = decode_rice(gb, 2) + (k & 1);
742 
743  // read coefficients 127 to opt_order
744  for (; k < opt_order; k++)
745  quant_cof[k] = decode_rice(gb, 1);
746 
747  quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
748 
749  if (opt_order > 1)
750  quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
751  }
752 
753  for (k = 2; k < opt_order; k++)
754  quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
755  }
756  }
757 
758  // read LTP gain and lag values
759  if (sconf->long_term_prediction) {
760  *bd->use_ltp = get_bits1(gb);
761 
762  if (*bd->use_ltp) {
763  int r, c;
764 
765  bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
766  bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
767 
768  r = get_unary(gb, 0, 4);
769  c = get_bits(gb, 2);
770  if (r >= 4) {
771  av_log(avctx, AV_LOG_ERROR, "r overflow\n");
772  return AVERROR_INVALIDDATA;
773  }
774 
775  bd->ltp_gain[2] = ltp_gain_values[r][c];
776 
777  bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
778  bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
779 
780  *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
781  *bd->ltp_lag += FFMAX(4, opt_order + 1);
782  }
783  }
784 
785  // read first value and residuals in case of a random access block
786  if (bd->ra_block) {
787  if (opt_order)
788  bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
789  if (opt_order > 1)
790  bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
791  if (opt_order > 2)
792  bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
793 
794  start = FFMIN(opt_order, 3);
795  }
796 
797  // read all residuals
798  if (sconf->bgmc) {
799  int delta[8];
800  unsigned int k [8];
801  unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
802 
803  // read most significant bits
804  unsigned int high;
805  unsigned int low;
806  unsigned int value;
807 
808  ff_bgmc_decode_init(gb, &high, &low, &value);
809 
810  current_res = bd->raw_samples + start;
811 
812  for (sb = 0; sb < sub_blocks; sb++) {
813  unsigned int sb_len = sb_length - (sb ? 0 : start);
814 
815  k [sb] = s[sb] > b ? s[sb] - b : 0;
816  delta[sb] = 5 - s[sb] + k[sb];
817 
818  ff_bgmc_decode(gb, sb_len, current_res,
819  delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
820 
821  current_res += sb_len;
822  }
823 
824  ff_bgmc_decode_end(gb);
825 
826 
827  // read least significant bits and tails
828  current_res = bd->raw_samples + start;
829 
830  for (sb = 0; sb < sub_blocks; sb++, start = 0) {
831  unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
832  unsigned int cur_k = k[sb];
833  unsigned int cur_s = s[sb];
834 
835  for (; start < sb_length; start++) {
836  int32_t res = *current_res;
837 
838  if (res == cur_tail_code) {
839  unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
840  << (5 - delta[sb]);
841 
842  res = decode_rice(gb, cur_s);
843 
844  if (res >= 0) {
845  res += (max_msb ) << cur_k;
846  } else {
847  res -= (max_msb - 1) << cur_k;
848  }
849  } else {
850  if (res > cur_tail_code)
851  res--;
852 
853  if (res & 1)
854  res = -res;
855 
856  res >>= 1;
857 
858  if (cur_k) {
859  res <<= cur_k;
860  res |= get_bits_long(gb, cur_k);
861  }
862  }
863 
864  *current_res++ = res;
865  }
866  }
867  } else {
868  current_res = bd->raw_samples + start;
869 
870  for (sb = 0; sb < sub_blocks; sb++, start = 0)
871  for (; start < sb_length; start++)
872  *current_res++ = decode_rice(gb, s[sb]);
873  }
874 
875  return 0;
876 }
877 
878 
879 /** Decode the block data for a non-constant block
880  */
881 static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
882 {
883  ALSSpecificConfig *sconf = &ctx->sconf;
884  unsigned int block_length = bd->block_length;
885  unsigned int smp = 0;
886  unsigned int k;
887  int opt_order = *bd->opt_order;
888  int sb;
889  int64_t y;
890  int32_t *quant_cof = bd->quant_cof;
891  int32_t *lpc_cof = bd->lpc_cof;
892  int32_t *raw_samples = bd->raw_samples;
893  int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
894  int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
895 
896  // reverse long-term prediction
897  if (*bd->use_ltp) {
898  int ltp_smp;
899 
900  for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
901  int center = ltp_smp - *bd->ltp_lag;
902  int begin = FFMAX(0, center - 2);
903  int end = center + 3;
904  int tab = 5 - (end - begin);
905  int base;
906 
907  y = 1 << 6;
908 
909  for (base = begin; base < end; base++, tab++)
910  y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
911 
912  raw_samples[ltp_smp] += y >> 7;
913  }
914  }
915 
916  // reconstruct all samples from residuals
917  if (bd->ra_block) {
918  for (smp = 0; smp < opt_order; smp++) {
919  y = 1 << 19;
920 
921  for (sb = 0; sb < smp; sb++)
922  y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
923 
924  *raw_samples++ -= y >> 20;
925  parcor_to_lpc(smp, quant_cof, lpc_cof);
926  }
927  } else {
928  for (k = 0; k < opt_order; k++)
929  parcor_to_lpc(k, quant_cof, lpc_cof);
930 
931  // store previous samples in case that they have to be altered
932  if (*bd->store_prev_samples)
933  memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
934  sizeof(*bd->prev_raw_samples) * sconf->max_order);
935 
936  // reconstruct difference signal for prediction (joint-stereo)
937  if (bd->js_blocks && bd->raw_other) {
938  int32_t *left, *right;
939 
940  if (bd->raw_other > raw_samples) { // D = R - L
941  left = raw_samples;
942  right = bd->raw_other;
943  } else { // D = R - L
944  left = bd->raw_other;
945  right = raw_samples;
946  }
947 
948  for (sb = -1; sb >= -sconf->max_order; sb--)
949  raw_samples[sb] = right[sb] - left[sb];
950  }
951 
952  // reconstruct shifted signal
953  if (*bd->shift_lsbs)
954  for (sb = -1; sb >= -sconf->max_order; sb--)
955  raw_samples[sb] >>= *bd->shift_lsbs;
956  }
957 
958  // reverse linear prediction coefficients for efficiency
959  lpc_cof = lpc_cof + opt_order;
960 
961  for (sb = 0; sb < opt_order; sb++)
962  lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
963 
964  // reconstruct raw samples
965  raw_samples = bd->raw_samples + smp;
966  lpc_cof = lpc_cof_reversed + opt_order;
967 
968  for (; raw_samples < raw_samples_end; raw_samples++) {
969  y = 1 << 19;
970 
971  for (sb = -opt_order; sb < 0; sb++)
972  y += MUL64(lpc_cof[sb], raw_samples[sb]);
973 
974  *raw_samples -= y >> 20;
975  }
976 
977  raw_samples = bd->raw_samples;
978 
979  // restore previous samples in case that they have been altered
980  if (*bd->store_prev_samples)
981  memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
982  sizeof(*raw_samples) * sconf->max_order);
983 
984  return 0;
985 }
986 
987 
988 /** Read the block data.
989  */
990 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
991 {
992  int ret;
993  GetBitContext *gb = &ctx->gb;
994  ALSSpecificConfig *sconf = &ctx->sconf;
995 
996  *bd->shift_lsbs = 0;
997  // read block type flag and read the samples accordingly
998  if (get_bits1(gb)) {
999  ret = read_var_block_data(ctx, bd);
1000  } else {
1001  ret = read_const_block_data(ctx, bd);
1002  }
1003 
1004  if (!sconf->mc_coding || ctx->js_switch)
1005  align_get_bits(gb);
1006 
1007  return ret;
1008 }
1009 
1010 
1011 /** Decode the block data.
1012  */
1013 static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1014 {
1015  unsigned int smp;
1016  int ret = 0;
1017 
1018  // read block type flag and read the samples accordingly
1019  if (*bd->const_block)
1020  decode_const_block_data(ctx, bd);
1021  else
1022  ret = decode_var_block_data(ctx, bd); // always return 0
1023 
1024  if (ret < 0)
1025  return ret;
1026 
1027  // TODO: read RLSLMS extension data
1028 
1029  if (*bd->shift_lsbs)
1030  for (smp = 0; smp < bd->block_length; smp++)
1031  bd->raw_samples[smp] <<= *bd->shift_lsbs;
1032 
1033  return 0;
1034 }
1035 
1036 
1037 /** Read and decode block data successively.
1038  */
1039 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1040 {
1041  int ret;
1042 
1043  if ((ret = read_block(ctx, bd)) < 0)
1044  return ret;
1045 
1046  return decode_block(ctx, bd);
1047 }
1048 
1049 
1050 /** Compute the number of samples left to decode for the current frame and
1051  * sets these samples to zero.
1052  */
1053 static void zero_remaining(unsigned int b, unsigned int b_max,
1054  const unsigned int *div_blocks, int32_t *buf)
1055 {
1056  unsigned int count = 0;
1057 
1058  while (b < b_max)
1059  count += div_blocks[b++];
1060 
1061  if (count)
1062  memset(buf, 0, sizeof(*buf) * count);
1063 }
1064 
1065 
1066 /** Decode blocks independently.
1067  */
1068 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1069  unsigned int c, const unsigned int *div_blocks,
1070  unsigned int *js_blocks)
1071 {
1072  int ret;
1073  unsigned int b;
1074  ALSBlockData bd = { 0 };
1075 
1076  bd.ra_block = ra_frame;
1077  bd.const_block = ctx->const_block;
1078  bd.shift_lsbs = ctx->shift_lsbs;
1079  bd.opt_order = ctx->opt_order;
1080  bd.store_prev_samples = ctx->store_prev_samples;
1081  bd.use_ltp = ctx->use_ltp;
1082  bd.ltp_lag = ctx->ltp_lag;
1083  bd.ltp_gain = ctx->ltp_gain[0];
1084  bd.quant_cof = ctx->quant_cof[0];
1085  bd.lpc_cof = ctx->lpc_cof[0];
1086  bd.prev_raw_samples = ctx->prev_raw_samples;
1087  bd.raw_samples = ctx->raw_samples[c];
1088 
1089 
1090  for (b = 0; b < ctx->num_blocks; b++) {
1091  bd.block_length = div_blocks[b];
1092 
1093  if ((ret = read_decode_block(ctx, &bd)) < 0) {
1094  // damaged block, write zero for the rest of the frame
1095  zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1096  return ret;
1097  }
1098  bd.raw_samples += div_blocks[b];
1099  bd.ra_block = 0;
1100  }
1101 
1102  return 0;
1103 }
1104 
1105 
1106 /** Decode blocks dependently.
1107  */
1108 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1109  unsigned int c, const unsigned int *div_blocks,
1110  unsigned int *js_blocks)
1111 {
1112  ALSSpecificConfig *sconf = &ctx->sconf;
1113  unsigned int offset = 0;
1114  unsigned int b;
1115  int ret;
1116  ALSBlockData bd[2] = { { 0 } };
1117 
1118  bd[0].ra_block = ra_frame;
1119  bd[0].const_block = ctx->const_block;
1120  bd[0].shift_lsbs = ctx->shift_lsbs;
1121  bd[0].opt_order = ctx->opt_order;
1122  bd[0].store_prev_samples = ctx->store_prev_samples;
1123  bd[0].use_ltp = ctx->use_ltp;
1124  bd[0].ltp_lag = ctx->ltp_lag;
1125  bd[0].ltp_gain = ctx->ltp_gain[0];
1126  bd[0].quant_cof = ctx->quant_cof[0];
1127  bd[0].lpc_cof = ctx->lpc_cof[0];
1128  bd[0].prev_raw_samples = ctx->prev_raw_samples;
1129  bd[0].js_blocks = *js_blocks;
1130 
1131  bd[1].ra_block = ra_frame;
1132  bd[1].const_block = ctx->const_block;
1133  bd[1].shift_lsbs = ctx->shift_lsbs;
1134  bd[1].opt_order = ctx->opt_order;
1135  bd[1].store_prev_samples = ctx->store_prev_samples;
1136  bd[1].use_ltp = ctx->use_ltp;
1137  bd[1].ltp_lag = ctx->ltp_lag;
1138  bd[1].ltp_gain = ctx->ltp_gain[0];
1139  bd[1].quant_cof = ctx->quant_cof[0];
1140  bd[1].lpc_cof = ctx->lpc_cof[0];
1141  bd[1].prev_raw_samples = ctx->prev_raw_samples;
1142  bd[1].js_blocks = *(js_blocks + 1);
1143 
1144  // decode all blocks
1145  for (b = 0; b < ctx->num_blocks; b++) {
1146  unsigned int s;
1147 
1148  bd[0].block_length = div_blocks[b];
1149  bd[1].block_length = div_blocks[b];
1150 
1151  bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1152  bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1153 
1154  bd[0].raw_other = bd[1].raw_samples;
1155  bd[1].raw_other = bd[0].raw_samples;
1156 
1157  if ((ret = read_decode_block(ctx, &bd[0])) < 0 ||
1158  (ret = read_decode_block(ctx, &bd[1])) < 0)
1159  goto fail;
1160 
1161  // reconstruct joint-stereo blocks
1162  if (bd[0].js_blocks) {
1163  if (bd[1].js_blocks)
1164  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair.\n");
1165 
1166  for (s = 0; s < div_blocks[b]; s++)
1167  bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1168  } else if (bd[1].js_blocks) {
1169  for (s = 0; s < div_blocks[b]; s++)
1170  bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1171  }
1172 
1173  offset += div_blocks[b];
1174  bd[0].ra_block = 0;
1175  bd[1].ra_block = 0;
1176  }
1177 
1178  // store carryover raw samples,
1179  // the others channel raw samples are stored by the calling function.
1180  memmove(ctx->raw_samples[c] - sconf->max_order,
1181  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1182  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1183 
1184  return 0;
1185 fail:
1186  // damaged block, write zero for the rest of the frame
1187  zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1188  zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1189  return ret;
1190 }
1191 
1192 static inline int als_weighting(GetBitContext *gb, int k, int off)
1193 {
1194  int idx = av_clip(decode_rice(gb, k) + off,
1195  0, FF_ARRAY_ELEMS(mcc_weightings) - 1);
1196  return mcc_weightings[idx];
1197 }
1198 
1199 /** Read the channel data.
1200  */
1201 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1202 {
1203  GetBitContext *gb = &ctx->gb;
1204  ALSChannelData *current = cd;
1205  unsigned int channels = ctx->avctx->channels;
1206  int entries = 0;
1207 
1208  while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1209  current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1210 
1211  if (current->master_channel >= channels) {
1212  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel.\n");
1213  return AVERROR_INVALIDDATA;
1214  }
1215 
1216  if (current->master_channel != c) {
1217  current->time_diff_flag = get_bits1(gb);
1218  current->weighting[0] = als_weighting(gb, 1, 16);
1219  current->weighting[1] = als_weighting(gb, 2, 14);
1220  current->weighting[2] = als_weighting(gb, 1, 16);
1221 
1222  if (current->time_diff_flag) {
1223  current->weighting[3] = als_weighting(gb, 1, 16);
1224  current->weighting[4] = als_weighting(gb, 1, 16);
1225  current->weighting[5] = als_weighting(gb, 1, 16);
1226 
1227  current->time_diff_sign = get_bits1(gb);
1228  current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1229  }
1230  }
1231 
1232  current++;
1233  entries++;
1234  }
1235 
1236  if (entries == channels) {
1237  av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data.\n");
1238  return AVERROR_INVALIDDATA;
1239  }
1240 
1241  align_get_bits(gb);
1242  return 0;
1243 }
1244 
1245 
1246 /** Recursively reverts the inter-channel correlation for a block.
1247  */
1248 static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1249  ALSChannelData **cd, int *reverted,
1250  unsigned int offset, int c)
1251 {
1252  ALSChannelData *ch = cd[c];
1253  unsigned int dep = 0;
1254  unsigned int channels = ctx->avctx->channels;
1255  unsigned int channel_size = ctx->sconf.frame_length + ctx->sconf.max_order;
1256 
1257  if (reverted[c])
1258  return 0;
1259 
1260  reverted[c] = 1;
1261 
1262  while (dep < channels && !ch[dep].stop_flag) {
1263  revert_channel_correlation(ctx, bd, cd, reverted, offset,
1264  ch[dep].master_channel);
1265 
1266  dep++;
1267  }
1268 
1269  if (dep == channels) {
1270  av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation.\n");
1271  return AVERROR_INVALIDDATA;
1272  }
1273 
1274  bd->const_block = ctx->const_block + c;
1275  bd->shift_lsbs = ctx->shift_lsbs + c;
1276  bd->opt_order = ctx->opt_order + c;
1277  bd->store_prev_samples = ctx->store_prev_samples + c;
1278  bd->use_ltp = ctx->use_ltp + c;
1279  bd->ltp_lag = ctx->ltp_lag + c;
1280  bd->ltp_gain = ctx->ltp_gain[c];
1281  bd->lpc_cof = ctx->lpc_cof[c];
1282  bd->quant_cof = ctx->quant_cof[c];
1283  bd->raw_samples = ctx->raw_samples[c] + offset;
1284 
1285  for (dep = 0; !ch[dep].stop_flag; dep++) {
1286  ptrdiff_t smp;
1287  ptrdiff_t begin = 1;
1288  ptrdiff_t end = bd->block_length - 1;
1289  int64_t y;
1290  int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1291 
1292  if (ch[dep].master_channel == c)
1293  continue;
1294 
1295  if (ch[dep].time_diff_flag) {
1296  int t = ch[dep].time_diff_index;
1297 
1298  if (ch[dep].time_diff_sign) {
1299  t = -t;
1300  if (begin < t) {
1301  av_log(ctx->avctx, AV_LOG_ERROR, "begin %"PTRDIFF_SPECIFIER" smaller than time diff index %d.\n", begin, t);
1302  return AVERROR_INVALIDDATA;
1303  }
1304  begin -= t;
1305  } else {
1306  if (end < t) {
1307  av_log(ctx->avctx, AV_LOG_ERROR, "end %"PTRDIFF_SPECIFIER" smaller than time diff index %d.\n", end, t);
1308  return AVERROR_INVALIDDATA;
1309  }
1310  end -= t;
1311  }
1312 
1313  if (FFMIN(begin - 1, begin - 1 + t) < ctx->raw_buffer - master ||
1314  FFMAX(end + 1, end + 1 + t) > ctx->raw_buffer + channels * channel_size - master) {
1315  av_log(ctx->avctx, AV_LOG_ERROR,
1316  "sample pointer range [%p, %p] not contained in raw_buffer [%p, %p].\n",
1317  master + FFMIN(begin - 1, begin - 1 + t), master + FFMAX(end + 1, end + 1 + t),
1318  ctx->raw_buffer, ctx->raw_buffer + channels * channel_size);
1319  return AVERROR_INVALIDDATA;
1320  }
1321 
1322  for (smp = begin; smp < end; smp++) {
1323  y = (1 << 6) +
1324  MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1325  MUL64(ch[dep].weighting[1], master[smp ]) +
1326  MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1327  MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1328  MUL64(ch[dep].weighting[4], master[smp + t]) +
1329  MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1330 
1331  bd->raw_samples[smp] += y >> 7;
1332  }
1333  } else {
1334 
1335  if (begin - 1 < ctx->raw_buffer - master ||
1336  end + 1 > 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 + begin - 1, master + end + 1,
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 
1350  bd->raw_samples[smp] += y >> 7;
1351  }
1352  }
1353  }
1354 
1355  return 0;
1356 }
1357 
1358 
1359 /** Read the frame data.
1360  */
1361 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1362 {
1363  ALSSpecificConfig *sconf = &ctx->sconf;
1364  AVCodecContext *avctx = ctx->avctx;
1365  GetBitContext *gb = &ctx->gb;
1366  unsigned int div_blocks[32]; ///< block sizes.
1367  unsigned int c;
1368  unsigned int js_blocks[2];
1369  uint32_t bs_info = 0;
1370  int ret;
1371 
1372  // skip the size of the ra unit if present in the frame
1373  if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1374  skip_bits_long(gb, 32);
1375 
1376  if (sconf->mc_coding && sconf->joint_stereo) {
1377  ctx->js_switch = get_bits1(gb);
1378  align_get_bits(gb);
1379  }
1380 
1381  if (!sconf->mc_coding || ctx->js_switch) {
1382  int independent_bs = !sconf->joint_stereo;
1383 
1384  for (c = 0; c < avctx->channels; c++) {
1385  js_blocks[0] = 0;
1386  js_blocks[1] = 0;
1387 
1388  get_block_sizes(ctx, div_blocks, &bs_info);
1389 
1390  // if joint_stereo and block_switching is set, independent decoding
1391  // is signaled via the first bit of bs_info
1392  if (sconf->joint_stereo && sconf->block_switching)
1393  if (bs_info >> 31)
1394  independent_bs = 2;
1395 
1396  // if this is the last channel, it has to be decoded independently
1397  if (c == avctx->channels - 1)
1398  independent_bs = 1;
1399 
1400  if (independent_bs) {
1401  ret = decode_blocks_ind(ctx, ra_frame, c,
1402  div_blocks, js_blocks);
1403  if (ret < 0)
1404  return ret;
1405  independent_bs--;
1406  } else {
1407  ret = decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks);
1408  if (ret < 0)
1409  return ret;
1410 
1411  c++;
1412  }
1413 
1414  // store carryover raw samples
1415  memmove(ctx->raw_samples[c] - sconf->max_order,
1416  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1417  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1418  }
1419  } else { // multi-channel coding
1420  ALSBlockData bd = { 0 };
1421  int b, ret;
1422  int *reverted_channels = ctx->reverted_channels;
1423  unsigned int offset = 0;
1424 
1425  for (c = 0; c < avctx->channels; c++)
1426  if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1427  av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data.\n");
1428  return AVERROR_INVALIDDATA;
1429  }
1430 
1431  memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1432 
1433  bd.ra_block = ra_frame;
1434  bd.prev_raw_samples = ctx->prev_raw_samples;
1435 
1436  get_block_sizes(ctx, div_blocks, &bs_info);
1437 
1438  for (b = 0; b < ctx->num_blocks; b++) {
1439  bd.block_length = div_blocks[b];
1440  if (bd.block_length <= 0) {
1441  av_log(ctx->avctx, AV_LOG_WARNING,
1442  "Invalid block length %u in channel data!\n",
1443  bd.block_length);
1444  continue;
1445  }
1446 
1447  for (c = 0; c < avctx->channels; c++) {
1448  bd.const_block = ctx->const_block + c;
1449  bd.shift_lsbs = ctx->shift_lsbs + c;
1450  bd.opt_order = ctx->opt_order + c;
1451  bd.store_prev_samples = ctx->store_prev_samples + c;
1452  bd.use_ltp = ctx->use_ltp + c;
1453  bd.ltp_lag = ctx->ltp_lag + c;
1454  bd.ltp_gain = ctx->ltp_gain[c];
1455  bd.lpc_cof = ctx->lpc_cof[c];
1456  bd.quant_cof = ctx->quant_cof[c];
1457  bd.raw_samples = ctx->raw_samples[c] + offset;
1458  bd.raw_other = NULL;
1459 
1460  if ((ret = read_block(ctx, &bd)) < 0)
1461  return ret;
1462  if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0)
1463  return ret;
1464  }
1465 
1466  for (c = 0; c < avctx->channels; c++) {
1467  ret = revert_channel_correlation(ctx, &bd, ctx->chan_data,
1468  reverted_channels, offset, c);
1469  if (ret < 0)
1470  return ret;
1471  }
1472  for (c = 0; c < avctx->channels; c++) {
1473  bd.const_block = ctx->const_block + c;
1474  bd.shift_lsbs = ctx->shift_lsbs + c;
1475  bd.opt_order = ctx->opt_order + c;
1476  bd.store_prev_samples = ctx->store_prev_samples + c;
1477  bd.use_ltp = ctx->use_ltp + c;
1478  bd.ltp_lag = ctx->ltp_lag + c;
1479  bd.ltp_gain = ctx->ltp_gain[c];
1480  bd.lpc_cof = ctx->lpc_cof[c];
1481  bd.quant_cof = ctx->quant_cof[c];
1482  bd.raw_samples = ctx->raw_samples[c] + offset;
1483 
1484  if ((ret = decode_block(ctx, &bd)) < 0)
1485  return ret;
1486  }
1487 
1488  memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1489  offset += div_blocks[b];
1490  bd.ra_block = 0;
1491  }
1492 
1493  // store carryover raw samples
1494  for (c = 0; c < avctx->channels; c++)
1495  memmove(ctx->raw_samples[c] - sconf->max_order,
1496  ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1497  sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1498  }
1499 
1500  // TODO: read_diff_float_data
1501 
1502  if (get_bits_left(gb) < 0) {
1503  av_log(ctx->avctx, AV_LOG_ERROR, "Overread %d\n", -get_bits_left(gb));
1504  return AVERROR_INVALIDDATA;
1505  }
1506 
1507  return 0;
1508 }
1509 
1510 
1511 /** Decode an ALS frame.
1512  */
1513 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1514  AVPacket *avpkt)
1515 {
1516  ALSDecContext *ctx = avctx->priv_data;
1517  AVFrame *frame = data;
1518  ALSSpecificConfig *sconf = &ctx->sconf;
1519  const uint8_t *buffer = avpkt->data;
1520  int buffer_size = avpkt->size;
1521  int invalid_frame, ret;
1522  unsigned int c, sample, ra_frame, bytes_read, shift;
1523 
1524  if ((ret = init_get_bits8(&ctx->gb, buffer, buffer_size)) < 0)
1525  return ret;
1526 
1527  // In the case that the distance between random access frames is set to zero
1528  // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1529  // For the first frame, if prediction is used, all samples used from the
1530  // previous frame are assumed to be zero.
1531  ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1532 
1533  // the last frame to decode might have a different length
1534  if (sconf->samples != 0xFFFFFFFF)
1535  ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1536  sconf->frame_length);
1537  else
1538  ctx->cur_frame_length = sconf->frame_length;
1539 
1540  // decode the frame data
1541  if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0)
1542  av_log(ctx->avctx, AV_LOG_WARNING,
1543  "Reading frame data failed. Skipping RA unit.\n");
1544 
1545  ctx->frame_id++;
1546 
1547  /* get output buffer */
1548  frame->nb_samples = ctx->cur_frame_length;
1549  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
1550  return ret;
1551 
1552  // transform decoded frame into output format
1553  #define INTERLEAVE_OUTPUT(bps) \
1554  { \
1555  int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \
1556  shift = bps - ctx->avctx->bits_per_raw_sample; \
1557  if (!ctx->cs_switch) { \
1558  for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1559  for (c = 0; c < avctx->channels; c++) \
1560  *dest++ = ctx->raw_samples[c][sample] << shift; \
1561  } else { \
1562  for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1563  for (c = 0; c < avctx->channels; c++) \
1564  *dest++ = ctx->raw_samples[sconf->chan_pos[c]][sample] << shift; \
1565  } \
1566  }
1567 
1568  if (ctx->avctx->bits_per_raw_sample <= 16) {
1569  INTERLEAVE_OUTPUT(16)
1570  } else {
1571  INTERLEAVE_OUTPUT(32)
1572  }
1573 
1574  // update CRC
1575  if (sconf->crc_enabled && (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
1576  int swap = HAVE_BIGENDIAN != sconf->msb_first;
1577 
1578  if (ctx->avctx->bits_per_raw_sample == 24) {
1579  int32_t *src = (int32_t *)frame->data[0];
1580 
1581  for (sample = 0;
1582  sample < ctx->cur_frame_length * avctx->channels;
1583  sample++) {
1584  int32_t v;
1585 
1586  if (swap)
1587  v = av_bswap32(src[sample]);
1588  else
1589  v = src[sample];
1590  if (!HAVE_BIGENDIAN)
1591  v >>= 8;
1592 
1593  ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1594  }
1595  } else {
1596  uint8_t *crc_source;
1597 
1598  if (swap) {
1599  if (ctx->avctx->bits_per_raw_sample <= 16) {
1600  int16_t *src = (int16_t*) frame->data[0];
1601  int16_t *dest = (int16_t*) ctx->crc_buffer;
1602  for (sample = 0;
1603  sample < ctx->cur_frame_length * avctx->channels;
1604  sample++)
1605  *dest++ = av_bswap16(src[sample]);
1606  } else {
1607  ctx->bdsp.bswap_buf((uint32_t *) ctx->crc_buffer,
1608  (uint32_t *) frame->data[0],
1609  ctx->cur_frame_length * avctx->channels);
1610  }
1611  crc_source = ctx->crc_buffer;
1612  } else {
1613  crc_source = frame->data[0];
1614  }
1615 
1616  ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1617  ctx->cur_frame_length * avctx->channels *
1618  av_get_bytes_per_sample(avctx->sample_fmt));
1619  }
1620 
1621 
1622  // check CRC sums if this is the last frame
1623  if (ctx->cur_frame_length != sconf->frame_length &&
1624  ctx->crc_org != ctx->crc) {
1625  av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1626  if (avctx->err_recognition & AV_EF_EXPLODE)
1627  return AVERROR_INVALIDDATA;
1628  }
1629  }
1630 
1631  *got_frame_ptr = 1;
1632 
1633  bytes_read = invalid_frame ? buffer_size :
1634  (get_bits_count(&ctx->gb) + 7) >> 3;
1635 
1636  return bytes_read;
1637 }
1638 
1639 
1640 /** Uninitialize the ALS decoder.
1641  */
1642 static av_cold int decode_end(AVCodecContext *avctx)
1643 {
1644  ALSDecContext *ctx = avctx->priv_data;
1645 
1646  av_freep(&ctx->sconf.chan_pos);
1647 
1648  ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1649 
1650  av_freep(&ctx->const_block);
1651  av_freep(&ctx->shift_lsbs);
1652  av_freep(&ctx->opt_order);
1653  av_freep(&ctx->store_prev_samples);
1654  av_freep(&ctx->use_ltp);
1655  av_freep(&ctx->ltp_lag);
1656  av_freep(&ctx->ltp_gain);
1657  av_freep(&ctx->ltp_gain_buffer);
1658  av_freep(&ctx->quant_cof);
1659  av_freep(&ctx->lpc_cof);
1660  av_freep(&ctx->quant_cof_buffer);
1661  av_freep(&ctx->lpc_cof_buffer);
1662  av_freep(&ctx->lpc_cof_reversed_buffer);
1663  av_freep(&ctx->prev_raw_samples);
1664  av_freep(&ctx->raw_samples);
1665  av_freep(&ctx->raw_buffer);
1666  av_freep(&ctx->chan_data);
1667  av_freep(&ctx->chan_data_buffer);
1668  av_freep(&ctx->reverted_channels);
1669  av_freep(&ctx->crc_buffer);
1670 
1671  return 0;
1672 }
1673 
1674 
1675 /** Initialize the ALS decoder.
1676  */
1677 static av_cold int decode_init(AVCodecContext *avctx)
1678 {
1679  unsigned int c;
1680  unsigned int channel_size;
1681  int num_buffers, ret;
1682  ALSDecContext *ctx = avctx->priv_data;
1683  ALSSpecificConfig *sconf = &ctx->sconf;
1684  ctx->avctx = avctx;
1685 
1686  if (!avctx->extradata) {
1687  av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1688  return AVERROR_INVALIDDATA;
1689  }
1690 
1691  if ((ret = read_specific_config(ctx)) < 0) {
1692  av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1693  goto fail;
1694  }
1695 
1696  if ((ret = check_specific_config(ctx)) < 0) {
1697  goto fail;
1698  }
1699 
1700  if (sconf->bgmc) {
1701  ret = ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1702  if (ret < 0)
1703  goto fail;
1704  }
1705  if (sconf->floating) {
1706  avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1707  avctx->bits_per_raw_sample = 32;
1708  } else {
1709  avctx->sample_fmt = sconf->resolution > 1
1710  ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
1711  avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1712  if (avctx->bits_per_raw_sample > 32) {
1713  av_log(avctx, AV_LOG_ERROR, "Bits per raw sample %d larger than 32.\n",
1714  avctx->bits_per_raw_sample);
1715  ret = AVERROR_INVALIDDATA;
1716  goto fail;
1717  }
1718  }
1719 
1720  // set maximum Rice parameter for progressive decoding based on resolution
1721  // This is not specified in 14496-3 but actually done by the reference
1722  // codec RM22 revision 2.
1723  ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1724 
1725  // set lag value for long-term prediction
1726  ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1727  (avctx->sample_rate >= 192000);
1728 
1729  // allocate quantized parcor coefficient buffer
1730  num_buffers = sconf->mc_coding ? avctx->channels : 1;
1731 
1732  ctx->quant_cof = av_malloc_array(num_buffers, sizeof(*ctx->quant_cof));
1733  ctx->lpc_cof = av_malloc_array(num_buffers, sizeof(*ctx->lpc_cof));
1734  ctx->quant_cof_buffer = av_malloc_array(num_buffers * sconf->max_order,
1735  sizeof(*ctx->quant_cof_buffer));
1736  ctx->lpc_cof_buffer = av_malloc_array(num_buffers * sconf->max_order,
1737  sizeof(*ctx->lpc_cof_buffer));
1738  ctx->lpc_cof_reversed_buffer = av_malloc_array(sconf->max_order,
1739  sizeof(*ctx->lpc_cof_buffer));
1740 
1741  if (!ctx->quant_cof || !ctx->lpc_cof ||
1742  !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1743  !ctx->lpc_cof_reversed_buffer) {
1744  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1745  ret = AVERROR(ENOMEM);
1746  goto fail;
1747  }
1748 
1749  // assign quantized parcor coefficient buffers
1750  for (c = 0; c < num_buffers; c++) {
1751  ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1752  ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1753  }
1754 
1755  // allocate and assign lag and gain data buffer for ltp mode
1756  ctx->const_block = av_malloc_array(num_buffers, sizeof(*ctx->const_block));
1757  ctx->shift_lsbs = av_malloc_array(num_buffers, sizeof(*ctx->shift_lsbs));
1758  ctx->opt_order = av_malloc_array(num_buffers, sizeof(*ctx->opt_order));
1759  ctx->store_prev_samples = av_malloc_array(num_buffers, sizeof(*ctx->store_prev_samples));
1760  ctx->use_ltp = av_mallocz_array(num_buffers, sizeof(*ctx->use_ltp));
1761  ctx->ltp_lag = av_malloc_array(num_buffers, sizeof(*ctx->ltp_lag));
1762  ctx->ltp_gain = av_malloc_array(num_buffers, sizeof(*ctx->ltp_gain));
1763  ctx->ltp_gain_buffer = av_malloc_array(num_buffers * 5, sizeof(*ctx->ltp_gain_buffer));
1764 
1765  if (!ctx->const_block || !ctx->shift_lsbs ||
1766  !ctx->opt_order || !ctx->store_prev_samples ||
1767  !ctx->use_ltp || !ctx->ltp_lag ||
1768  !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1769  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1770  ret = AVERROR(ENOMEM);
1771  goto fail;
1772  }
1773 
1774  for (c = 0; c < num_buffers; c++)
1775  ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1776 
1777  // allocate and assign channel data buffer for mcc mode
1778  if (sconf->mc_coding) {
1779  ctx->chan_data_buffer = av_mallocz_array(num_buffers * num_buffers,
1780  sizeof(*ctx->chan_data_buffer));
1781  ctx->chan_data = av_mallocz_array(num_buffers,
1782  sizeof(*ctx->chan_data));
1783  ctx->reverted_channels = av_malloc_array(num_buffers,
1784  sizeof(*ctx->reverted_channels));
1785 
1786  if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1787  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1788  ret = AVERROR(ENOMEM);
1789  goto fail;
1790  }
1791 
1792  for (c = 0; c < num_buffers; c++)
1793  ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
1794  } else {
1795  ctx->chan_data = NULL;
1796  ctx->chan_data_buffer = NULL;
1797  ctx->reverted_channels = NULL;
1798  }
1799 
1800  channel_size = sconf->frame_length + sconf->max_order;
1801 
1802  ctx->prev_raw_samples = av_malloc_array(sconf->max_order, sizeof(*ctx->prev_raw_samples));
1803  ctx->raw_buffer = av_mallocz_array(avctx->channels * channel_size, sizeof(*ctx->raw_buffer));
1804  ctx->raw_samples = av_malloc_array(avctx->channels, sizeof(*ctx->raw_samples));
1805 
1806  // allocate previous raw sample buffer
1807  if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1808  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1809  ret = AVERROR(ENOMEM);
1810  goto fail;
1811  }
1812 
1813  // assign raw samples buffers
1814  ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1815  for (c = 1; c < avctx->channels; c++)
1816  ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1817 
1818  // allocate crc buffer
1819  if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
1820  (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL))) {
1821  ctx->crc_buffer = av_malloc_array(ctx->cur_frame_length *
1822  avctx->channels *
1823  av_get_bytes_per_sample(avctx->sample_fmt),
1824  sizeof(*ctx->crc_buffer));
1825  if (!ctx->crc_buffer) {
1826  av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1827  ret = AVERROR(ENOMEM);
1828  goto fail;
1829  }
1830  }
1831 
1832  ff_bswapdsp_init(&ctx->bdsp);
1833 
1834  return 0;
1835 
1836 fail:
1837  decode_end(avctx);
1838  return ret;
1839 }
1840 
1841 
1842 /** Flush (reset) the frame ID after seeking.
1843  */
1844 static av_cold void flush(AVCodecContext *avctx)
1845 {
1846  ALSDecContext *ctx = avctx->priv_data;
1847 
1848  ctx->frame_id = 0;
1849 }
1850 
1851 
1852 AVCodec ff_als_decoder = {
1853  .name = "als",
1854  .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),
1855  .type = AVMEDIA_TYPE_AUDIO,
1856  .id = AV_CODEC_ID_MP4ALS,
1857  .priv_data_size = sizeof(ALSDecContext),
1858  .init = decode_init,
1859  .close = decode_end,
1860  .decode = decode_frame,
1861  .flush = flush,
1862  .capabilities = AV_CODEC_CAP_SUBFRAMES | AV_CODEC_CAP_DR1,
1863 };
MUL64
#define MUL64(a, b)
Definition: mathops.h:53
BswapDSPContext::bswap_buf
void(* bswap_buf)(uint32_t *dst, const uint32_t *src, int w)
Definition: bswapdsp.h:25
ff_als_decoder
AVCodec ff_als_decoder
Definition: alsdec.c:1852
als_weighting
static int als_weighting(GetBitContext *gb, int k, int off)
Definition: alsdec.c:1192
decode_var_block_data
static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
Decode the block data for a non-constant block.
Definition: alsdec.c:881
ALSSpecificConfig::msb_first
int msb_first
1 = original CRC calculated on big-endian system, 0 = little-endian
Definition: alsdec.c:159
NULL
#define NULL
Definition: coverity.c:32
val
const char const char void * val
Definition: avisynth_c.h:634
s
const char * s
Definition: avisynth_c.h:631
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
shift
static int shift(int a, int b)
Definition: sonic.c:82
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:184
ALSDecContext::use_ltp
int * use_ltp
contains use_ltp flags for all channels
Definition: alsdec.c:212
data
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
ff_bgmc_end
av_cold void ff_bgmc_end(uint8_t **cf_lut, int **cf_lut_status)
Release the lookup table arrays.
Definition: bgmc.c:480
ALSDecContext::raw_samples
int32_t ** raw_samples
decoded raw samples for each channel
Definition: alsdec.c:225
ALSDecContext::crc_buffer
uint8_t * crc_buffer
buffer of byte order corrected samples used for CRC check
Definition: alsdec.c:227
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:247
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
mcc_weightings
static const int16_t mcc_weightings[]
Inter-channel weighting factors for multi-channel correlation.
Definition: alsdec.c:118
skip_bits_long
static void skip_bits_long(GetBitContext *s, int n)
Definition: get_bits.h:204
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
ALSSpecificConfig::block_switching
int block_switching
number of block switching levels
Definition: alsdec.c:167
ALSSpecificConfig::rlslms
int rlslms
use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
Definition: alsdec.c:174
AVPacket::size
int size
Definition: avcodec.h:1581
b
const char * b
Definition: vf_curves.c:109
check_specific_config
static int check_specific_config(ALSDecContext *ctx)
Check the ALSSpecificConfig for unsupported features.
Definition: alsdec.c:429
av_bswap16
#define av_bswap16
Definition: bswap.h:31
ALSSpecificConfig::adapt_order
int adapt_order
adaptive order: 1 = on, 0 = off
Definition: alsdec.c:163
read_frame_data
static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
Read the frame data.
Definition: alsdec.c:1361
ALSDecContext::lpc_cof_reversed_buffer
int32_t * lpc_cof_reversed_buffer
temporary buffer to set up a reversed versio of lpc_cof_buffer
Definition: alsdec.c:220
ALSDecContext::gb
GetBitContext gb
Definition: alsdec.c:194
bgmc.h
Block Gilbert-Moore decoder header.
master
const char * master
Definition: vf_curves.c:110
ALSDecContext::js_switch
unsigned int js_switch
if true, joint-stereo decoding is enforced
Definition: alsdec.c:201
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:3049
read_decode_block
static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
Read and decode block data successively.
Definition: alsdec.c:1039
INTERLEAVE_OUTPUT
#define INTERLEAVE_OUTPUT(bps)
AV_SAMPLE_FMT_FLT
float
Definition: samplefmt.h:63
sample
#define sample
Definition: flacdsp_template.c:44
AVCodec
AVCodec.
Definition: avcodec.h:3542
decode_rice
static int32_t decode_rice(GetBitContext *gb, unsigned int k)
Read and decode a Rice codeword.
Definition: alsdec.c:477
get_sbits_long
static int get_sbits_long(GetBitContext *s, int n)
Read 0-32 bits as a signed integer.
Definition: get_bits.h:370
ALSDecContext::ltp_lag
int * ltp_lag
contains ltp lag values for all channels
Definition: alsdec.c:213
ALSDecContext::const_block
int * const_block
contains const_block flags for all channels
Definition: alsdec.c:208
ltp_gain_values
static const uint8_t ltp_gain_values[4][4]
Gain values of p(0) for long-term prediction.
Definition: alsdec.c:107
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Initialize the ALS decoder.
Definition: alsdec.c:1677
ALSDecContext::bdsp
BswapDSPContext bdsp
Definition: alsdec.c:195
ALSBlockData::lpc_cof
int32_t * lpc_cof
coefficients of the direct form prediction
Definition: alsdec.c:243
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:2418
uint8_t
uint8_t
Definition: audio_convert.c:194
av_cold
#define av_cold
Definition: attributes.h:82
AV_CRC_32_IEEE_LE
Definition: crc.h:42
decode_const_block_data
static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
Decode the block data for a constant block.
Definition: alsdec.c:598
delta
float delta
Definition: vorbis_enc_data.h:457
end
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
ALSDecContext::ltp_gain
int ** ltp_gain
gain values for ltp 5-tap filter for a channel
Definition: alsdec.c:214
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1764
ALSSpecificConfig::chan_sort
int chan_sort
channel rearrangement: 1 = on, 0 = off
Definition: alsdec.c:173
frame
static AVFrame * frame
Definition: demuxing_decoding.c:53
ALSSpecificConfig::joint_stereo
int joint_stereo
joint stereo: 1 = on, 0 = off
Definition: alsdec.c:170
AVPacket::data
uint8_t * data
Definition: avcodec.h:1580
get_bits_count
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:199
ff_dlog
#define ff_dlog(a,...)
Definition: tableprint_vlc.h:29
get_bits.h
bitstream reader API header.
decode_blocks_ind
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:1068
ff_bgmc_decode_init
void 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
ALSBlockData::block_length
unsigned int block_length
number of samples within the block
Definition: alsdec.c:232
zero_remaining
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:1053
ALSSpecificConfig::ra_distance
int ra_distance
distance between RA frames (in frames, 0...255)
Definition: alsdec.c:161
ALSChannelData::weighting
int weighting[6]
Definition: alsdec.c:187
ALSDecContext::quant_cof_buffer
int32_t * quant_cof_buffer
contains all quantized parcor coefficients
Definition: alsdec.c:217
AV_SAMPLE_FMT_S32
signed 32 bits
Definition: samplefmt.h:62
ALSDecContext::chan_data_buffer
ALSChannelData * chan_data_buffer
contains channel data for all channels
Definition: alsdec.c:222
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
ALSSpecificConfig::bgmc
int bgmc
"Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
Definition: alsdec.c:168
ALSDecContext::cs_switch
unsigned int cs_switch
if true, channel rearrangement is done
Definition: alsdec.c:202
get_bits_left
static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:568
ALSBlockData::use_ltp
int * use_ltp
if true, long-term prediction is used
Definition: alsdec.c:239
ALSSpecificConfig::ra_flag
enum RA_Flag ra_flag
indicates where the size of ra units is stored
Definition: alsdec.c:162
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
ALSDecContext::ltp_lag_length
int ltp_lag_length
number of bits used for ltp lag value
Definition: alsdec.c:207
PTRDIFF_SPECIFIER
#define PTRDIFF_SPECIFIER
Definition: internal.h:251
AVERROR
#define AVERROR(e)
Definition: error.h:43
dprint_specific_config
static av_cold void dprint_specific_config(ALSDecContext *ctx)
Definition: alsdec.c:250
ALSBlockData::opt_order
unsigned int * opt_order
prediction order of this block
Definition: alsdec.c:237
ALSSpecificConfig::chan_pos
int * chan_pos
original channel positions
Definition: alsdec.c:176
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
ALSDecContext::avctx
AVCodecContext * avctx
Definition: alsdec.c:192
parcor_scaled_values
static const int16_t parcor_scaled_values[]
Scaled PARCOR values used for the first two PARCOR coefficients.
Definition: alsdec.c:68
r
const char * r
Definition: vf_curves.c:107
ALSDecContext::lpc_cof
int32_t ** lpc_cof
coefficients of the direct form prediction filter for a channel
Definition: alsdec.c:218
ALSSpecificConfig::chan_config_info
int chan_config_info
mapping of channels to loudspeaker locations. Unused until setting channel configuration is implement...
Definition: alsdec.c:175
ALSDecContext::num_blocks
unsigned int num_blocks
number of blocks used in the current frame
Definition: alsdec.c:203
AVMEDIA_TYPE_AUDIO
Definition: avutil.h:194
AVCodec::name
const char * name
Name of the codec implementation.
Definition: avcodec.h:3549
ALSDecContext::prev_raw_samples
int32_t * prev_raw_samples
contains unshifted raw samples from the previous block
Definition: alsdec.c:224
decode_blocks
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:1108
ff_bgmc_decode_end
void ff_bgmc_decode_end(GetBitContext *gb)
Finish decoding.
Definition: bgmc.c:498
ALSDecContext::crc_table
const AVCRC * crc_table
Definition: alsdec.c:196
offset
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
count
GLsizei count
Definition: opengl_enc.c:109
FFMAX
#define FFMAX(a, b)
Definition: common.h:94
ALSDecContext::bgmc_lut_status
int * bgmc_lut_status
pointer at lookup table status flags used for BGMC
Definition: alsdec.c:206
fail
#define fail()
Definition: checkasm.h:81
ALSDecContext::sconf
ALSSpecificConfig sconf
Definition: alsdec.c:193
ALSBlockData::store_prev_samples
int * store_prev_samples
if true, carryover samples have to be stored
Definition: alsdec.c:238
ALSDecContext::shift_lsbs
unsigned int * shift_lsbs
contains shift_lsbs flags for all channels
Definition: alsdec.c:209
AVCodecContext::err_recognition
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:2936
FFMIN
#define FFMIN(a, b)
Definition: common.h:96
read_var_block_data
static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
Read the block data for a non-constant block.
Definition: alsdec.c:612
value
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:109
ALSSpecificConfig::chan_config
int chan_config
indicates that a chan_config_info field is present
Definition: alsdec.c:172
int32_t
int32_t
Definition: audio_convert.c:194
ctx
AVFormatContext * ctx
Definition: movenc.c:48
av_crc
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:357
ff_bgmc_decode
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:505
decode_end
static av_cold int decode_end(AVCodecContext *avctx)
Uninitialize the ALS decoder.
Definition: alsdec.c:1642
ALSBlockData::const_block
int * const_block
if true, this is a constant value block
Definition: alsdec.c:234
AV_EF_EXPLODE
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: avcodec.h:2947
n
int n
Definition: avisynth_c.h:547
ALSSpecificConfig::floating
int floating
1 = IEEE 32-bit floating-point, 0 = integer
Definition: alsdec.c:158
ALSChannelData::time_diff_flag
int time_diff_flag
Definition: alsdec.c:184
ALSChannelData::master_channel
int master_channel
Definition: alsdec.c:183
ALSDecContext::crc
uint32_t crc
CRC value calculated from decoded data.
Definition: alsdec.c:198
src
#define src
Definition: vp9dsp.c:530
ALSSpecificConfig::coef_table
int coef_table
table index of Rice code parameters
Definition: alsdec.c:164
read_const_block_data
static int read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
Read the block data for a constant block.
Definition: alsdec.c:568
FF_ARRAY_ELEMS
#define FF_ARRAY_ELEMS(a)
Definition: sinewin_tablegen_template.c:36
ALSSpecificConfig::sb_part
int sb_part
sub-block partition
Definition: alsdec.c:169
ALSBlockData::raw_other
int32_t * raw_other
decoded raw samples of the other channel of a channel pair
Definition: alsdec.c:246
ALSDecContext::bgmc_lut
uint8_t * bgmc_lut
pointer at lookup tables used for BGMC
Definition: alsdec.c:205
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
ALSBlockData::ltp_gain
int * ltp_gain
gain values for ltp 5-tap filter
Definition: alsdec.c:241
ALSBlockData::js_blocks
int js_blocks
true if this block contains a difference signal
Definition: alsdec.c:235
av_bswap32
#define av_bswap32
Definition: bswap.h:33
ALSBlockData::ra_block
unsigned int ra_block
if true, this is a random access block
Definition: alsdec.c:233
avcodec.h
Libavcodec external API header.
parcor_to_lpc
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:495
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:2410
init_get_bits8
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:437
AVCodecContext
main external API structure.
Definition: avcodec.h:1649
ALSDecContext::chan_data
ALSChannelData ** chan_data
channel data for multi-channel correlation
Definition: alsdec.c:221
decode_frame
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Decode an ALS frame.
Definition: alsdec.c:1513
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:928
MISSING_ERR
#define MISSING_ERR(cond, str, errval)
buf
void * buf
Definition: avisynth_c.h:553
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:1765
AV_EF_CAREFUL
#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:2950
get_bits1
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:299
skip_bits1
static void skip_bits1(GetBitContext *s)
Definition: get_bits.h:324
ALSDecContext::s_max
unsigned int s_max
maximum Rice parameter allowed in entropy coding
Definition: alsdec.c:204
skip_bits
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:292
AV_CODEC_CAP_SUBFRAMES
#define AV_CODEC_CAP_SUBFRAMES
Codec can output multiple frames per AVPacket Normally demuxers return one frame at a time...
Definition: avcodec.h:1006
ALSBlockData::ltp_lag
int * ltp_lag
lag value for long-term prediction
Definition: alsdec.c:240
ALSDecContext::lpc_cof_buffer
int32_t * lpc_cof_buffer
contains all coefficients of the direct form prediction filter
Definition: alsdec.c:219
AV_EF_CRCCHECK
#define AV_EF_CRCCHECK
Verify checksums embedded in the bitstream (could be of either encoded or decoded data...
Definition: avcodec.h:2944
parcor_rice_table
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:47
RA_Flag
RA_Flag
Definition: alsdec.c:148
read_specific_config
static av_cold int read_specific_config(ALSDecContext *ctx)
Read an ALSSpecificConfig from a buffer into the output struct.
Definition: alsdec.c:280
get_bits_long
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition: get_bits.h:332
ALSSpecificConfig::long_term_prediction
int long_term_prediction
long term prediction (LTP): 1 = on, 0 = off
Definition: alsdec.c:165
ALSBlockData::raw_samples
int32_t * raw_samples
decoded raw samples / residuals for this block
Definition: alsdec.c:244
ALSDecContext::reverted_channels
int * reverted_channels
stores a flag for each reverted channel
Definition: alsdec.c:223
ALSDecContext::opt_order
unsigned int * opt_order
contains opt_order flags for all channels
Definition: alsdec.c:210
ALSDecContext::raw_buffer
int32_t * raw_buffer
contains all decoded raw samples including carryover samples
Definition: alsdec.c:226
ALSSpecificConfig::max_order
int max_order
maximum prediction order (0..1023)
Definition: alsdec.c:166
ALSSpecificConfig::samples
uint32_t samples
number of samples, 0xFFFFFFFF if unknown
Definition: alsdec.c:156
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:198
av_get_bytes_per_sample
int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt)
Return number of bytes per sample.
Definition: samplefmt.c:104
av_crc_get_table
const AVCRC * av_crc_get_table(AVCRCId crc_id)
Get an initialized standard CRC table.
Definition: crc.c:343
decode
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
Definition: ccaption_dec.c:722
ALSSpecificConfig::mc_coding
int mc_coding
extended inter-channel coding (multi channel coding): 1 = on, 0 = off
Definition: alsdec.c:171
tail_code
static const uint8_t tail_code[16][6]
Tail codes used in arithmetic coding using block Gilbert-Moore codes.
Definition: alsdec.c:128
internal.h
common internal api header.
if
if(ret< 0)
Definition: vf_mcdeint.c:282
ALSBlockData::prev_raw_samples
int32_t * prev_raw_samples
contains unshifted raw samples from the previous block
Definition: alsdec.c:245
get_unary
static int get_unary(GetBitContext *gb, int stop, int len)
Get unary code of limited length.
Definition: unary.h:33
flush
static av_cold void flush(AVCodecContext *avctx)
Flush (reset) the frame ID after seeking.
Definition: alsdec.c:1844
AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:61
c
static double c[64]
Definition: vsrc_mptestsrc.c:87
ALSChannelData::time_diff_index
int time_diff_index
Definition: alsdec.c:186
ALSDecContext::ltp_gain_buffer
int * ltp_gain_buffer
contains all gain values for ltp 5-tap filter
Definition: alsdec.c:215
ALSBlockData::quant_cof
int32_t * quant_cof
quantized parcor coefficients
Definition: alsdec.c:242
avpriv_mpeg4audio_get_config
int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, int bit_size, int sync_extension)
Parse MPEG-4 systems extradata to retrieve audio configuration.
Definition: mpeg4audio.c:81
MKBETAG
#define MKBETAG(a, b, c, d)
Definition: common.h:343
parse_bs_info
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:454
ff_bswapdsp_init
av_cold void ff_bswapdsp_init(BswapDSPContext *c)
Definition: bswapdsp.c:49
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:1691
ALSDecContext::quant_cof
int32_t ** quant_cof
quantized parcor coefficients for a channel
Definition: alsdec.c:216
AVCodecContext::channels
int channels
number of audio channels
Definition: avcodec.h:2411
ALSSpecificConfig::crc_enabled
int crc_enabled
enable Cyclic Redundancy Checksum
Definition: alsdec.c:177
ALSDecContext::crc_org
uint32_t crc_org
CRC value of the original input data.
Definition: alsdec.c:197
decode_block
static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
Decode the block data.
Definition: alsdec.c:1013
AV_CODEC_ID_MP4ALS
Definition: avcodec.h:562
read_block
static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
Read the block data.
Definition: alsdec.c:990
ALSSpecificConfig::frame_length
int frame_length
frame length for each frame (last frame may differ)
Definition: alsdec.c:160
align_get_bits
static const uint8_t * align_get_bits(GetBitContext *s)
Definition: get_bits.h:445
ALSChannelData::stop_flag
int stop_flag
Definition: alsdec.c:182
tab
static const struct twinvq_data tab
Definition: twinvq_data.h:11135
ALSBlockData::shift_lsbs
unsigned int * shift_lsbs
shift of values for this block
Definition: alsdec.c:236
av_mallocz_array
static void * av_mallocz_array(size_t nmemb, size_t size)
Definition: mem.h:229
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
start
void INT64 start
Definition: avisynth_c.h:553
ff_bgmc_init
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
av_malloc_array
#define av_malloc_array(a, b)
Definition: tableprint_vlc.h:32
read_channel_data
static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
Read the channel data.
Definition: alsdec.c:1201
get_block_sizes
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:515
ALSDecContext::store_prev_samples
int * store_prev_samples
contains store_prev_samples flags for all channels
Definition: alsdec.c:211
ALSDecContext::frame_id
unsigned int frame_id
the frame ID / number of the current frame
Definition: alsdec.c:200
revert_channel_correlation
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:1248
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1557
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:241
AVCRC
uint32_t AVCRC
Definition: crc.h:35
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:956
for
for(j=16;j >0;--j)
Definition: h264pred_template.c:469
ALSDecContext::cur_frame_length
unsigned int cur_frame_length
length of the current frame to decode
Definition: alsdec.c:199
buffer
GLuint buffer
Definition: opengl_enc.c:102
ALSSpecificConfig::resolution
int resolution
000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
Definition: alsdec.c:157
ALSChannelData::time_diff_sign
int time_diff_sign
Definition: alsdec.c:185
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