f356a7010487503a2188dab1183b252dbe655b2d
[libav.git] / libavcodec / alsdec.c
1 /*
2 * MPEG-4 ALS decoder
3 * Copyright (c) 2009 Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
4 *
5 * This file is part of Libav.
6 *
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * MPEG-4 ALS decoder
25 * @author Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
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 num_blocks; ///< number of blocks used in the current frame
203 unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding
204 uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
205 int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
206 int ltp_lag_length; ///< number of bits used for ltp lag value
207 int *const_block; ///< contains const_block flags for all channels
208 unsigned int *shift_lsbs; ///< contains shift_lsbs flags for all channels
209 unsigned int *opt_order; ///< contains opt_order flags for all channels
210 int *store_prev_samples; ///< contains store_prev_samples flags for all channels
211 int *use_ltp; ///< contains use_ltp flags for all channels
212 int *ltp_lag; ///< contains ltp lag values for all channels
213 int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
214 int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
215 int32_t **quant_cof; ///< quantized parcor coefficients for a channel
216 int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
217 int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
218 int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
219 int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
220 ALSChannelData **chan_data; ///< channel data for multi-channel correlation
221 ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
222 int *reverted_channels; ///< stores a flag for each reverted channel
223 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
224 int32_t **raw_samples; ///< decoded raw samples for each channel
225 int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
226 uint8_t *crc_buffer; ///< buffer of byte order corrected samples used for CRC check
227 } ALSDecContext;
228
229
230 typedef struct ALSBlockData {
231 unsigned int block_length; ///< number of samples within the block
232 unsigned int ra_block; ///< if true, this is a random access block
233 int *const_block; ///< if true, this is a constant value block
234 int js_blocks; ///< true if this block contains a difference signal
235 unsigned int *shift_lsbs; ///< shift of values for this block
236 unsigned int *opt_order; ///< prediction order of this block
237 int *store_prev_samples;///< if true, carryover samples have to be stored
238 int *use_ltp; ///< if true, long-term prediction is used
239 int *ltp_lag; ///< lag value for long-term prediction
240 int *ltp_gain; ///< gain values for ltp 5-tap filter
241 int32_t *quant_cof; ///< quantized parcor coefficients
242 int32_t *lpc_cof; ///< coefficients of the direct form prediction
243 int32_t *raw_samples; ///< decoded raw samples / residuals for this block
244 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
245 int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
246 } ALSBlockData;
247
248
249 static av_cold void dprint_specific_config(ALSDecContext *ctx)
250 {
251 #ifdef DEBUG
252 AVCodecContext *avctx = ctx->avctx;
253 ALSSpecificConfig *sconf = &ctx->sconf;
254
255 ff_dlog(avctx, "resolution = %i\n", sconf->resolution);
256 ff_dlog(avctx, "floating = %i\n", sconf->floating);
257 ff_dlog(avctx, "frame_length = %i\n", sconf->frame_length);
258 ff_dlog(avctx, "ra_distance = %i\n", sconf->ra_distance);
259 ff_dlog(avctx, "ra_flag = %i\n", sconf->ra_flag);
260 ff_dlog(avctx, "adapt_order = %i\n", sconf->adapt_order);
261 ff_dlog(avctx, "coef_table = %i\n", sconf->coef_table);
262 ff_dlog(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
263 ff_dlog(avctx, "max_order = %i\n", sconf->max_order);
264 ff_dlog(avctx, "block_switching = %i\n", sconf->block_switching);
265 ff_dlog(avctx, "bgmc = %i\n", sconf->bgmc);
266 ff_dlog(avctx, "sb_part = %i\n", sconf->sb_part);
267 ff_dlog(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
268 ff_dlog(avctx, "mc_coding = %i\n", sconf->mc_coding);
269 ff_dlog(avctx, "chan_config = %i\n", sconf->chan_config);
270 ff_dlog(avctx, "chan_sort = %i\n", sconf->chan_sort);
271 ff_dlog(avctx, "RLSLMS = %i\n", sconf->rlslms);
272 ff_dlog(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
273 #endif
274 }
275
276
277 /** Read an ALSSpecificConfig from a buffer into the output struct.
278 */
279 static av_cold int read_specific_config(ALSDecContext *ctx)
280 {
281 GetBitContext gb;
282 uint64_t ht_size;
283 int i, config_offset;
284 MPEG4AudioConfig m4ac;
285 ALSSpecificConfig *sconf = &ctx->sconf;
286 AVCodecContext *avctx = ctx->avctx;
287 uint32_t als_id, header_size, trailer_size;
288
289 init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
290
291 config_offset = avpriv_mpeg4audio_get_config(&m4ac, avctx->extradata,
292 avctx->extradata_size * 8, 1);
293
294 if (config_offset < 0)
295 return AVERROR_INVALIDDATA;
296
297 skip_bits_long(&gb, config_offset);
298
299 if (get_bits_left(&gb) < (30 << 3))
300 return AVERROR_INVALIDDATA;
301
302 // read the fixed items
303 als_id = get_bits_long(&gb, 32);
304 avctx->sample_rate = m4ac.sample_rate;
305 skip_bits_long(&gb, 32); // sample rate already known
306 sconf->samples = get_bits_long(&gb, 32);
307 avctx->channels = m4ac.channels;
308 skip_bits(&gb, 16); // number of channels already known
309 skip_bits(&gb, 3); // skip file_type
310 sconf->resolution = get_bits(&gb, 3);
311 sconf->floating = get_bits1(&gb);
312 sconf->msb_first = get_bits1(&gb);
313 sconf->frame_length = get_bits(&gb, 16) + 1;
314 sconf->ra_distance = get_bits(&gb, 8);
315 sconf->ra_flag = get_bits(&gb, 2);
316 sconf->adapt_order = get_bits1(&gb);
317 sconf->coef_table = get_bits(&gb, 2);
318 sconf->long_term_prediction = get_bits1(&gb);
319 sconf->max_order = get_bits(&gb, 10);
320 sconf->block_switching = get_bits(&gb, 2);
321 sconf->bgmc = get_bits1(&gb);
322 sconf->sb_part = get_bits1(&gb);
323 sconf->joint_stereo = get_bits1(&gb);
324 sconf->mc_coding = get_bits1(&gb);
325 sconf->chan_config = get_bits1(&gb);
326 sconf->chan_sort = get_bits1(&gb);
327 sconf->crc_enabled = get_bits1(&gb);
328 sconf->rlslms = get_bits1(&gb);
329 skip_bits(&gb, 5); // skip 5 reserved bits
330 skip_bits1(&gb); // skip aux_data_enabled
331
332
333 // check for ALSSpecificConfig struct
334 if (als_id != MKBETAG('A','L','S','\0'))
335 return AVERROR_INVALIDDATA;
336
337 ctx->cur_frame_length = sconf->frame_length;
338
339 // read channel config
340 if (sconf->chan_config)
341 sconf->chan_config_info = get_bits(&gb, 16);
342 // TODO: use this to set avctx->channel_layout
343
344
345 // read channel sorting
346 if (sconf->chan_sort && avctx->channels > 1) {
347 int chan_pos_bits = av_ceil_log2(avctx->channels);
348 int bits_needed = avctx->channels * chan_pos_bits + 7;
349 if (get_bits_left(&gb) < bits_needed)
350 return AVERROR_INVALIDDATA;
351
352 if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
353 return AVERROR(ENOMEM);
354
355 for (i = 0; i < avctx->channels; i++)
356 sconf->chan_pos[i] = get_bits(&gb, chan_pos_bits);
357
358 align_get_bits(&gb);
359 // TODO: use this to actually do channel sorting
360 } else {
361 sconf->chan_sort = 0;
362 }
363
364
365 // read fixed header and trailer sizes,
366 // if size = 0xFFFFFFFF then there is no data field!
367 if (get_bits_left(&gb) < 64)
368 return AVERROR_INVALIDDATA;
369
370 header_size = get_bits_long(&gb, 32);
371 trailer_size = get_bits_long(&gb, 32);
372 if (header_size == 0xFFFFFFFF)
373 header_size = 0;
374 if (trailer_size == 0xFFFFFFFF)
375 trailer_size = 0;
376
377 ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
378
379
380 // skip the header and trailer data
381 if (get_bits_left(&gb) < ht_size)
382 return AVERROR_INVALIDDATA;
383
384 if (ht_size > INT32_MAX)
385 return AVERROR_PATCHWELCOME;
386
387 skip_bits_long(&gb, ht_size);
388
389
390 // initialize CRC calculation
391 if (sconf->crc_enabled) {
392 if (get_bits_left(&gb) < 32)
393 return AVERROR_INVALIDDATA;
394
395 if (avctx->err_recognition & AV_EF_CRCCHECK) {
396 ctx->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);
397 ctx->crc = 0xFFFFFFFF;
398 ctx->crc_org = ~get_bits_long(&gb, 32);
399 } else
400 skip_bits_long(&gb, 32);
401 }
402
403
404 // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
405
406 dprint_specific_config(ctx);
407
408 return 0;
409 }
410
411
412 /** Check the ALSSpecificConfig for unsupported features.
413 */
414 static int check_specific_config(ALSDecContext *ctx)
415 {
416 ALSSpecificConfig *sconf = &ctx->sconf;
417 int error = 0;
418
419 // report unsupported feature and set error value
420 #define MISSING_ERR(cond, str, errval) \
421 { \
422 if (cond) { \
423 avpriv_report_missing_feature(ctx->avctx, \
424 str); \
425 error = errval; \
426 } \
427 }
428
429 MISSING_ERR(sconf->floating, "Floating point decoding", AVERROR_PATCHWELCOME);
430 MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", AVERROR_PATCHWELCOME);
431 MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
432
433 return error;
434 }
435
436
437 /** Parse the bs_info field to extract the block partitioning used in
438 * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
439 */
440 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
441 unsigned int div, unsigned int **div_blocks,
442 unsigned int *num_blocks)
443 {
444 if (n < 31 && ((bs_info << n) & 0x40000000)) {
445 // if the level is valid and the investigated bit n is set
446 // then recursively check both children at bits (2n+1) and (2n+2)
447 n *= 2;
448 div += 1;
449 parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
450 parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
451 } else {
452 // else the bit is not set or the last level has been reached
453 // (bit implicitly not set)
454 **div_blocks = div;
455 (*div_blocks)++;
456 (*num_blocks)++;
457 }
458 }
459
460
461 /** Read and decode a Rice codeword.
462 */
463 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
464 {
465 int max = get_bits_left(gb) - k;
466 int q = get_unary(gb, 0, max);
467 int r = k ? get_bits1(gb) : !(q & 1);
468
469 if (k > 1) {
470 q <<= (k - 1);
471 q += get_bits_long(gb, k - 1);
472 } else if (!k) {
473 q >>= 1;
474 }
475 return r ? q : ~q;
476 }
477
478
479 /** Convert PARCOR coefficient k to direct filter coefficient.
480 */
481 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
482 {
483 int i, j;
484
485 for (i = 0, j = k - 1; i < j; i++, j--) {
486 int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
487 cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
488 cof[i] += tmp1;
489 }
490 if (i == j)
491 cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
492
493 cof[k] = par[k];
494 }
495
496
497 /** Read block switching field if necessary and set actual block sizes.
498 * Also assure that the block sizes of the last frame correspond to the
499 * actual number of samples.
500 */
501 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
502 uint32_t *bs_info)
503 {
504 ALSSpecificConfig *sconf = &ctx->sconf;
505 GetBitContext *gb = &ctx->gb;
506 unsigned int *ptr_div_blocks = div_blocks;
507 unsigned int b;
508
509 if (sconf->block_switching) {
510 unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
511 *bs_info = get_bits_long(gb, bs_info_len);
512 *bs_info <<= (32 - bs_info_len);
513 }
514
515 ctx->num_blocks = 0;
516 parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
517
518 // The last frame may have an overdetermined block structure given in
519 // the bitstream. In that case the defined block structure would need
520 // more samples than available to be consistent.
521 // The block structure is actually used but the block sizes are adapted
522 // to fit the actual number of available samples.
523 // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
524 // This results in the actual block sizes: 2 2 1 0.
525 // This is not specified in 14496-3 but actually done by the reference
526 // codec RM22 revision 2.
527 // This appears to happen in case of an odd number of samples in the last
528 // frame which is actually not allowed by the block length switching part
529 // of 14496-3.
530 // The ALS conformance files feature an odd number of samples in the last
531 // frame.
532
533 for (b = 0; b < ctx->num_blocks; b++)
534 div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
535
536 if (ctx->cur_frame_length != ctx->sconf.frame_length) {
537 unsigned int remaining = ctx->cur_frame_length;
538
539 for (b = 0; b < ctx->num_blocks; b++) {
540 if (remaining <= div_blocks[b]) {
541 div_blocks[b] = remaining;
542 ctx->num_blocks = b + 1;
543 break;
544 }
545
546 remaining -= div_blocks[b];
547 }
548 }
549 }
550
551
552 /** Read the block data for a constant block
553 */
554 static void read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
555 {
556 ALSSpecificConfig *sconf = &ctx->sconf;
557 AVCodecContext *avctx = ctx->avctx;
558 GetBitContext *gb = &ctx->gb;
559
560 *bd->raw_samples = 0;
561 *bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
562 bd->js_blocks = get_bits1(gb);
563
564 // skip 5 reserved bits
565 skip_bits(gb, 5);
566
567 if (*bd->const_block) {
568 unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
569 *bd->raw_samples = get_sbits_long(gb, const_val_bits);
570 }
571
572 // ensure constant block decoding by reusing this field
573 *bd->const_block = 1;
574 }
575
576
577 /** Decode the block data for a constant block
578 */
579 static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
580 {
581 int smp = bd->block_length - 1;
582 int32_t val = *bd->raw_samples;
583 int32_t *dst = bd->raw_samples + 1;
584
585 // write raw samples into buffer
586 for (; smp; smp--)
587 *dst++ = val;
588 }
589
590
591 /** Read the block data for a non-constant block
592 */
593 static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
594 {
595 ALSSpecificConfig *sconf = &ctx->sconf;
596 AVCodecContext *avctx = ctx->avctx;
597 GetBitContext *gb = &ctx->gb;
598 unsigned int k;
599 unsigned int s[8];
600 unsigned int sx[8];
601 unsigned int sub_blocks, log2_sub_blocks, sb_length;
602 unsigned int start = 0;
603 unsigned int opt_order;
604 int sb;
605 int32_t *quant_cof = bd->quant_cof;
606 int32_t *current_res;
607
608
609 // ensure variable block decoding by reusing this field
610 *bd->const_block = 0;
611
612 *bd->opt_order = 1;
613 bd->js_blocks = get_bits1(gb);
614
615 opt_order = *bd->opt_order;
616
617 // determine the number of subblocks for entropy decoding
618 if (!sconf->bgmc && !sconf->sb_part) {
619 log2_sub_blocks = 0;
620 } else {
621 if (sconf->bgmc && sconf->sb_part)
622 log2_sub_blocks = get_bits(gb, 2);
623 else
624 log2_sub_blocks = 2 * get_bits1(gb);
625 }
626
627 sub_blocks = 1 << log2_sub_blocks;
628
629 // do not continue in case of a damaged stream since
630 // block_length must be evenly divisible by sub_blocks
631 if (bd->block_length & (sub_blocks - 1)) {
632 av_log(avctx, AV_LOG_WARNING,
633 "Block length is not evenly divisible by the number of subblocks.\n");
634 return AVERROR_INVALIDDATA;
635 }
636
637 sb_length = bd->block_length >> log2_sub_blocks;
638
639 if (sconf->bgmc) {
640 s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
641 for (k = 1; k < sub_blocks; k++)
642 s[k] = s[k - 1] + decode_rice(gb, 2);
643
644 for (k = 0; k < sub_blocks; k++) {
645 sx[k] = s[k] & 0x0F;
646 s [k] >>= 4;
647 }
648 } else {
649 s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
650 for (k = 1; k < sub_blocks; k++)
651 s[k] = s[k - 1] + decode_rice(gb, 0);
652 }
653 for (k = 1; k < sub_blocks; k++)
654 if (s[k] > 32) {
655 av_log(avctx, AV_LOG_ERROR, "k invalid for rice code.\n");
656 return AVERROR_INVALIDDATA;
657 }
658
659 if (get_bits1(gb))
660 *bd->shift_lsbs = get_bits(gb, 4) + 1;
661
662 *bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || *bd->shift_lsbs;
663
664
665 if (!sconf->rlslms) {
666 if (sconf->adapt_order && sconf->max_order) {
667 int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
668 2, sconf->max_order + 1));
669 *bd->opt_order = get_bits(gb, opt_order_length);
670 if (*bd->opt_order > sconf->max_order) {
671 *bd->opt_order = sconf->max_order;
672 av_log(avctx, AV_LOG_ERROR, "Predictor order too large!\n");
673 return AVERROR_INVALIDDATA;
674 }
675 } else {
676 *bd->opt_order = sconf->max_order;
677 }
678
679 opt_order = *bd->opt_order;
680
681 if (opt_order) {
682 int add_base;
683
684 if (sconf->coef_table == 3) {
685 add_base = 0x7F;
686
687 // read coefficient 0
688 quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
689
690 // read coefficient 1
691 if (opt_order > 1)
692 quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
693
694 // read coefficients 2 to opt_order
695 for (k = 2; k < opt_order; k++)
696 quant_cof[k] = get_bits(gb, 7);
697 } else {
698 int k_max;
699 add_base = 1;
700
701 // read coefficient 0 to 19
702 k_max = FFMIN(opt_order, 20);
703 for (k = 0; k < k_max; k++) {
704 int rice_param = parcor_rice_table[sconf->coef_table][k][1];
705 int offset = parcor_rice_table[sconf->coef_table][k][0];
706 quant_cof[k] = decode_rice(gb, rice_param) + offset;
707 if (quant_cof[k] < -64 || quant_cof[k] > 63) {
708 av_log(avctx, AV_LOG_ERROR,
709 "quant_cof %"PRIu32" is out of range\n",
710 quant_cof[k]);
711 return AVERROR_INVALIDDATA;
712 }
713 }
714
715 // read coefficients 20 to 126
716 k_max = FFMIN(opt_order, 127);
717 for (; k < k_max; k++)
718 quant_cof[k] = decode_rice(gb, 2) + (k & 1);
719
720 // read coefficients 127 to opt_order
721 for (; k < opt_order; k++)
722 quant_cof[k] = decode_rice(gb, 1);
723
724 quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
725
726 if (opt_order > 1)
727 quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
728 }
729
730 for (k = 2; k < opt_order; k++)
731 quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
732 }
733 }
734
735 // read LTP gain and lag values
736 if (sconf->long_term_prediction) {
737 *bd->use_ltp = get_bits1(gb);
738
739 if (*bd->use_ltp) {
740 int r, c;
741
742 bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
743 bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
744
745 r = get_unary(gb, 0, 3);
746 c = get_bits(gb, 2);
747 bd->ltp_gain[2] = ltp_gain_values[r][c];
748
749 bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
750 bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
751
752 *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
753 *bd->ltp_lag += FFMAX(4, opt_order + 1);
754 }
755 }
756
757 // read first value and residuals in case of a random access block
758 if (bd->ra_block) {
759 if (opt_order)
760 bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
761 if (opt_order > 1)
762 bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
763 if (opt_order > 2)
764 bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
765
766 start = FFMIN(opt_order, 3);
767 }
768
769 // read all residuals
770 if (sconf->bgmc) {
771 int delta[8];
772 unsigned int k [8];
773 unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
774
775 // read most significant bits
776 unsigned int high;
777 unsigned int low;
778 unsigned int value;
779
780 ff_bgmc_decode_init(gb, &high, &low, &value);
781
782 current_res = bd->raw_samples + start;
783
784 for (sb = 0; sb < sub_blocks; sb++) {
785 unsigned int sb_len = sb_length - (sb ? 0 : start);
786
787 k [sb] = s[sb] > b ? s[sb] - b : 0;
788 delta[sb] = 5 - s[sb] + k[sb];
789
790 ff_bgmc_decode(gb, sb_len, current_res,
791 delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
792
793 current_res += sb_len;
794 }
795
796 ff_bgmc_decode_end(gb);
797
798
799 // read least significant bits and tails
800 current_res = bd->raw_samples + start;
801
802 for (sb = 0; sb < sub_blocks; sb++, start = 0) {
803 unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
804 unsigned int cur_k = k[sb];
805 unsigned int cur_s = s[sb];
806
807 for (; start < sb_length; start++) {
808 int32_t res = *current_res;
809
810 if (res == cur_tail_code) {
811 unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
812 << (5 - delta[sb]);
813
814 res = decode_rice(gb, cur_s);
815
816 if (res >= 0) {
817 res += (max_msb ) << cur_k;
818 } else {
819 res -= (max_msb - 1) << cur_k;
820 }
821 } else {
822 if (res > cur_tail_code)
823 res--;
824
825 if (res & 1)
826 res = -res;
827
828 res >>= 1;
829
830 if (cur_k) {
831 res <<= cur_k;
832 res |= get_bits_long(gb, cur_k);
833 }
834 }
835
836 *current_res++ = res;
837 }
838 }
839 } else {
840 current_res = bd->raw_samples + start;
841
842 for (sb = 0; sb < sub_blocks; sb++, start = 0)
843 for (; start < sb_length; start++)
844 *current_res++ = decode_rice(gb, s[sb]);
845 }
846
847 if (!sconf->mc_coding || ctx->js_switch)
848 align_get_bits(gb);
849
850 return 0;
851 }
852
853
854 /** Decode the block data for a non-constant block
855 */
856 static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
857 {
858 ALSSpecificConfig *sconf = &ctx->sconf;
859 unsigned int block_length = bd->block_length;
860 unsigned int smp = 0;
861 unsigned int k;
862 int opt_order = *bd->opt_order;
863 int sb;
864 int64_t y;
865 int32_t *quant_cof = bd->quant_cof;
866 int32_t *lpc_cof = bd->lpc_cof;
867 int32_t *raw_samples = bd->raw_samples;
868 int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
869 int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
870
871 // reverse long-term prediction
872 if (*bd->use_ltp) {
873 int ltp_smp;
874
875 for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
876 int center = ltp_smp - *bd->ltp_lag;
877 int begin = FFMAX(0, center - 2);
878 int end = center + 3;
879 int tab = 5 - (end - begin);
880 int base;
881
882 y = 1 << 6;
883
884 for (base = begin; base < end; base++, tab++)
885 y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
886
887 raw_samples[ltp_smp] += y >> 7;
888 }
889 }
890
891 // reconstruct all samples from residuals
892 if (bd->ra_block) {
893 for (smp = 0; smp < opt_order; smp++) {
894 y = 1 << 19;
895
896 for (sb = 0; sb < smp; sb++)
897 y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
898
899 *raw_samples++ -= y >> 20;
900 parcor_to_lpc(smp, quant_cof, lpc_cof);
901 }
902 } else {
903 for (k = 0; k < opt_order; k++)
904 parcor_to_lpc(k, quant_cof, lpc_cof);
905
906 // store previous samples in case that they have to be altered
907 if (*bd->store_prev_samples)
908 memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
909 sizeof(*bd->prev_raw_samples) * sconf->max_order);
910
911 // reconstruct difference signal for prediction (joint-stereo)
912 if (bd->js_blocks && bd->raw_other) {
913 int32_t *left, *right;
914
915 if (bd->raw_other > raw_samples) { // D = R - L
916 left = raw_samples;
917 right = bd->raw_other;
918 } else { // D = R - L
919 left = bd->raw_other;
920 right = raw_samples;
921 }
922
923 for (sb = -1; sb >= -sconf->max_order; sb--)
924 raw_samples[sb] = right[sb] - left[sb];
925 }
926
927 // reconstruct shifted signal
928 if (*bd->shift_lsbs)
929 for (sb = -1; sb >= -sconf->max_order; sb--)
930 raw_samples[sb] >>= *bd->shift_lsbs;
931 }
932
933 // reverse linear prediction coefficients for efficiency
934 lpc_cof = lpc_cof + opt_order;
935
936 for (sb = 0; sb < opt_order; sb++)
937 lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
938
939 // reconstruct raw samples
940 raw_samples = bd->raw_samples + smp;
941 lpc_cof = lpc_cof_reversed + opt_order;
942
943 for (; raw_samples < raw_samples_end; raw_samples++) {
944 y = 1 << 19;
945
946 for (sb = -opt_order; sb < 0; sb++)
947 y += MUL64(lpc_cof[sb], raw_samples[sb]);
948
949 *raw_samples -= y >> 20;
950 }
951
952 raw_samples = bd->raw_samples;
953
954 // restore previous samples in case that they have been altered
955 if (*bd->store_prev_samples)
956 memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
957 sizeof(*raw_samples) * sconf->max_order);
958
959 return 0;
960 }
961
962
963 /** Read the block data.
964 */
965 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
966 {
967 int ret = 0;
968 GetBitContext *gb = &ctx->gb;
969
970 *bd->shift_lsbs = 0;
971 // read block type flag and read the samples accordingly
972 if (get_bits1(gb)) {
973 ret = read_var_block_data(ctx, bd);
974 } else {
975 read_const_block_data(ctx, bd);
976 }
977
978 return ret;
979 }
980
981
982 /** Decode the block data.
983 */
984 static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
985 {
986 unsigned int smp;
987 int ret = 0;
988
989 // read block type flag and read the samples accordingly
990 if (*bd->const_block)
991 decode_const_block_data(ctx, bd);
992 else
993 ret = decode_var_block_data(ctx, bd); // always return 0
994
995 if (ret < 0)
996 return ret;
997
998 // TODO: read RLSLMS extension data
999
1000 if (*bd->shift_lsbs)
1001 for (smp = 0; smp < bd->block_length; smp++)
1002 bd->raw_samples[smp] <<= *bd->shift_lsbs;
1003
1004 return 0;
1005 }
1006
1007
1008 /** Read and decode block data successively.
1009 */
1010 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
1011 {
1012 int ret;
1013
1014 if ((ret = read_block(ctx, bd)) < 0)
1015 return ret;
1016
1017 return decode_block(ctx, bd);
1018 }
1019
1020
1021 /** Compute the number of samples left to decode for the current frame and
1022 * sets these samples to zero.
1023 */
1024 static void zero_remaining(unsigned int b, unsigned int b_max,
1025 const unsigned int *div_blocks, int32_t *buf)
1026 {
1027 unsigned int count = 0;
1028
1029 for (; b < b_max; b++)
1030 count += div_blocks[b];
1031
1032 if (count)
1033 memset(buf, 0, sizeof(*buf) * count);
1034 }
1035
1036
1037 /** Decode blocks independently.
1038 */
1039 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1040 unsigned int c, const unsigned int *div_blocks,
1041 unsigned int *js_blocks)
1042 {
1043 int ret;
1044 unsigned int b;
1045 ALSBlockData bd = { 0 };
1046
1047 bd.ra_block = ra_frame;
1048 bd.const_block = ctx->const_block;
1049 bd.shift_lsbs = ctx->shift_lsbs;
1050 bd.opt_order = ctx->opt_order;
1051 bd.store_prev_samples = ctx->store_prev_samples;
1052 bd.use_ltp = ctx->use_ltp;
1053 bd.ltp_lag = ctx->ltp_lag;
1054 bd.ltp_gain = ctx->ltp_gain[0];
1055 bd.quant_cof = ctx->quant_cof[0];
1056 bd.lpc_cof = ctx->lpc_cof[0];
1057 bd.prev_raw_samples = ctx->prev_raw_samples;
1058 bd.raw_samples = ctx->raw_samples[c];
1059
1060
1061 for (b = 0; b < ctx->num_blocks; b++) {
1062 bd.block_length = div_blocks[b];
1063
1064 if ((ret = read_decode_block(ctx, &bd)) < 0) {
1065 // damaged block, write zero for the rest of the frame
1066 zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1067 return ret;
1068 }
1069 bd.raw_samples += div_blocks[b];
1070 bd.ra_block = 0;
1071 }
1072
1073 return 0;
1074 }
1075
1076
1077 /** Decode blocks dependently.
1078 */
1079 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1080 unsigned int c, const unsigned int *div_blocks,
1081 unsigned int *js_blocks)
1082 {
1083 ALSSpecificConfig *sconf = &ctx->sconf;
1084 unsigned int offset = 0;
1085 unsigned int b;
1086 int ret;
1087 ALSBlockData bd[2] = { { 0 } };
1088
1089 bd[0].ra_block = ra_frame;
1090 bd[0].const_block = ctx->const_block;
1091 bd[0].shift_lsbs = ctx->shift_lsbs;
1092 bd[0].opt_order = ctx->opt_order;
1093 bd[0].store_prev_samples = ctx->store_prev_samples;
1094 bd[0].use_ltp = ctx->use_ltp;
1095 bd[0].ltp_lag = ctx->ltp_lag;
1096 bd[0].ltp_gain = ctx->ltp_gain[0];
1097 bd[0].quant_cof = ctx->quant_cof[0];
1098 bd[0].lpc_cof = ctx->lpc_cof[0];
1099 bd[0].prev_raw_samples = ctx->prev_raw_samples;
1100 bd[0].js_blocks = *js_blocks;
1101
1102 bd[1].ra_block = ra_frame;
1103 bd[1].const_block = ctx->const_block;
1104 bd[1].shift_lsbs = ctx->shift_lsbs;
1105 bd[1].opt_order = ctx->opt_order;
1106 bd[1].store_prev_samples = ctx->store_prev_samples;
1107 bd[1].use_ltp = ctx->use_ltp;
1108 bd[1].ltp_lag = ctx->ltp_lag;
1109 bd[1].ltp_gain = ctx->ltp_gain[0];
1110 bd[1].quant_cof = ctx->quant_cof[0];
1111 bd[1].lpc_cof = ctx->lpc_cof[0];
1112 bd[1].prev_raw_samples = ctx->prev_raw_samples;
1113 bd[1].js_blocks = *(js_blocks + 1);
1114
1115 // decode all blocks
1116 for (b = 0; b < ctx->num_blocks; b++) {
1117 unsigned int s;
1118
1119 bd[0].block_length = div_blocks[b];
1120 bd[1].block_length = div_blocks[b];
1121
1122 bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1123 bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1124
1125 bd[0].raw_other = bd[1].raw_samples;
1126 bd[1].raw_other = bd[0].raw_samples;
1127
1128 if ((ret = read_decode_block(ctx, &bd[0])) < 0 ||
1129 (ret = read_decode_block(ctx, &bd[1])) < 0)
1130 goto fail;
1131
1132 // reconstruct joint-stereo blocks
1133 if (bd[0].js_blocks) {
1134 if (bd[1].js_blocks)
1135 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair!\n");
1136
1137 for (s = 0; s < div_blocks[b]; s++)
1138 bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1139 } else if (bd[1].js_blocks) {
1140 for (s = 0; s < div_blocks[b]; s++)
1141 bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1142 }
1143
1144 offset += div_blocks[b];
1145 bd[0].ra_block = 0;
1146 bd[1].ra_block = 0;
1147 }
1148
1149 // store carryover raw samples,
1150 // the others channel raw samples are stored by the calling function.
1151 memmove(ctx->raw_samples[c] - sconf->max_order,
1152 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1153 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1154
1155 return 0;
1156 fail:
1157 // damaged block, write zero for the rest of the frame
1158 zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1159 zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1160 return ret;
1161 }
1162
1163 static inline int als_weighting(GetBitContext *gb, int k, int off)
1164 {
1165 int idx = av_clip(decode_rice(gb, k) + off,
1166 0, FF_ARRAY_ELEMS(mcc_weightings) - 1);
1167 return mcc_weightings[idx];
1168 }
1169
1170 /** Read the channel data.
1171 */
1172 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1173 {
1174 GetBitContext *gb = &ctx->gb;
1175 ALSChannelData *current = cd;
1176 unsigned int channels = ctx->avctx->channels;
1177 int entries = 0;
1178
1179 while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1180 current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1181
1182 if (current->master_channel >= channels) {
1183 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel!\n");
1184 return AVERROR_INVALIDDATA;
1185 }
1186
1187 if (current->master_channel != c) {
1188 current->time_diff_flag = get_bits1(gb);
1189 current->weighting[0] = als_weighting(gb, 1, 16);
1190 current->weighting[1] = als_weighting(gb, 2, 14);
1191 current->weighting[2] = als_weighting(gb, 1, 16);
1192
1193 if (current->time_diff_flag) {
1194 current->weighting[3] = als_weighting(gb, 1, 16);
1195 current->weighting[4] = als_weighting(gb, 1, 16);
1196 current->weighting[5] = als_weighting(gb, 1, 16);
1197
1198 current->time_diff_sign = get_bits1(gb);
1199 current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1200 }
1201 }
1202
1203 current++;
1204 entries++;
1205 }
1206
1207 if (entries == channels) {
1208 av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data!\n");
1209 return AVERROR_INVALIDDATA;
1210 }
1211
1212 align_get_bits(gb);
1213 return 0;
1214 }
1215
1216
1217 /** Recursively reverts the inter-channel correlation for a block.
1218 */
1219 static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1220 ALSChannelData **cd, int *reverted,
1221 unsigned int offset, int c)
1222 {
1223 ALSChannelData *ch = cd[c];
1224 unsigned int dep = 0;
1225 unsigned int channels = ctx->avctx->channels;
1226 unsigned int channel_size = ctx->sconf.frame_length + ctx->sconf.max_order;
1227
1228 if (reverted[c])
1229 return 0;
1230
1231 reverted[c] = 1;
1232
1233 while (dep < channels && !ch[dep].stop_flag) {
1234 revert_channel_correlation(ctx, bd, cd, reverted, offset,
1235 ch[dep].master_channel);
1236
1237 dep++;
1238 }
1239
1240 if (dep == channels) {
1241 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation!\n");
1242 return AVERROR_INVALIDDATA;
1243 }
1244
1245 bd->const_block = ctx->const_block + c;
1246 bd->shift_lsbs = ctx->shift_lsbs + c;
1247 bd->opt_order = ctx->opt_order + c;
1248 bd->store_prev_samples = ctx->store_prev_samples + c;
1249 bd->use_ltp = ctx->use_ltp + c;
1250 bd->ltp_lag = ctx->ltp_lag + c;
1251 bd->ltp_gain = ctx->ltp_gain[c];
1252 bd->lpc_cof = ctx->lpc_cof[c];
1253 bd->quant_cof = ctx->quant_cof[c];
1254 bd->raw_samples = ctx->raw_samples[c] + offset;
1255
1256 dep = 0;
1257 while (!ch[dep].stop_flag) {
1258 ptrdiff_t smp;
1259 ptrdiff_t begin = 1;
1260 ptrdiff_t end = bd->block_length - 1;
1261 int64_t y;
1262 int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1263
1264 if (ch[dep].time_diff_flag) {
1265 int t = ch[dep].time_diff_index;
1266
1267 if (ch[dep].time_diff_sign) {
1268 t = -t;
1269 begin -= t;
1270 } else {
1271 end -= t;
1272 }
1273
1274 if (FFMIN(begin - 1, begin - 1 + t) < ctx->raw_buffer - master ||
1275 FFMAX(end + 1, end + 1 + t) > ctx->raw_buffer + channels * channel_size - master) {
1276 av_log(ctx->avctx, AV_LOG_ERROR,
1277 "sample pointer range [%p, %p] not contained in raw_buffer [%p, %p].\n",
1278 master + FFMIN(begin - 1, begin - 1 + t), master + FFMAX(end + 1, end + 1 + t),
1279 ctx->raw_buffer, ctx->raw_buffer + channels * channel_size);
1280 return AVERROR_INVALIDDATA;
1281 }
1282
1283 for (smp = begin; smp < end; smp++) {
1284 y = (1 << 6) +
1285 MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1286 MUL64(ch[dep].weighting[1], master[smp ]) +
1287 MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1288 MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1289 MUL64(ch[dep].weighting[4], master[smp + t]) +
1290 MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1291
1292 bd->raw_samples[smp] += y >> 7;
1293 }
1294 } else {
1295
1296 if (begin - 1 < ctx->raw_buffer - master ||
1297 end + 1 > ctx->raw_buffer + channels * channel_size - master) {
1298 av_log(ctx->avctx, AV_LOG_ERROR,
1299 "sample pointer range [%p, %p] not contained in raw_buffer [%p, %p].\n",
1300 master + begin - 1, master + end + 1,
1301 ctx->raw_buffer, ctx->raw_buffer + channels * channel_size);
1302 return AVERROR_INVALIDDATA;
1303 }
1304
1305 for (smp = begin; smp < end; smp++) {
1306 y = (1 << 6) +
1307 MUL64(ch[dep].weighting[0], master[smp - 1]) +
1308 MUL64(ch[dep].weighting[1], master[smp ]) +
1309 MUL64(ch[dep].weighting[2], master[smp + 1]);
1310
1311 bd->raw_samples[smp] += y >> 7;
1312 }
1313 }
1314
1315 dep++;
1316 }
1317
1318 return 0;
1319 }
1320
1321
1322 /** Read the frame data.
1323 */
1324 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1325 {
1326 ALSSpecificConfig *sconf = &ctx->sconf;
1327 AVCodecContext *avctx = ctx->avctx;
1328 GetBitContext *gb = &ctx->gb;
1329 unsigned int div_blocks[32]; ///< block sizes.
1330 unsigned int c;
1331 unsigned int js_blocks[2];
1332 uint32_t bs_info = 0;
1333 int ret;
1334
1335 // skip the size of the ra unit if present in the frame
1336 if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1337 skip_bits_long(gb, 32);
1338
1339 if (sconf->mc_coding && sconf->joint_stereo) {
1340 ctx->js_switch = get_bits1(gb);
1341 align_get_bits(gb);
1342 }
1343
1344 if (!sconf->mc_coding || ctx->js_switch) {
1345 int independent_bs = !sconf->joint_stereo;
1346
1347 for (c = 0; c < avctx->channels; c++) {
1348 js_blocks[0] = 0;
1349 js_blocks[1] = 0;
1350
1351 get_block_sizes(ctx, div_blocks, &bs_info);
1352
1353 // if joint_stereo and block_switching is set, independent decoding
1354 // is signaled via the first bit of bs_info
1355 if (sconf->joint_stereo && sconf->block_switching)
1356 if (bs_info >> 31)
1357 independent_bs = 2;
1358
1359 // if this is the last channel, it has to be decoded independently
1360 if (c == avctx->channels - 1)
1361 independent_bs = 1;
1362
1363 if (independent_bs) {
1364 ret = decode_blocks_ind(ctx, ra_frame, c,
1365 div_blocks, js_blocks);
1366 if (ret < 0)
1367 return ret;
1368 independent_bs--;
1369 } else {
1370 ret = decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks);
1371 if (ret < 0)
1372 return ret;
1373
1374 c++;
1375 }
1376
1377 // store carryover raw samples
1378 memmove(ctx->raw_samples[c] - sconf->max_order,
1379 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1380 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1381 }
1382 } else { // multi-channel coding
1383 ALSBlockData bd = { 0 };
1384 int b, ret;
1385 int *reverted_channels = ctx->reverted_channels;
1386 unsigned int offset = 0;
1387
1388 for (c = 0; c < avctx->channels; c++)
1389 if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1390 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data!\n");
1391 return AVERROR_INVALIDDATA;
1392 }
1393
1394 memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1395
1396 bd.ra_block = ra_frame;
1397 bd.prev_raw_samples = ctx->prev_raw_samples;
1398
1399 get_block_sizes(ctx, div_blocks, &bs_info);
1400
1401 for (b = 0; b < ctx->num_blocks; b++) {
1402 bd.block_length = div_blocks[b];
1403 if (bd.block_length <= 0) {
1404 av_log(ctx->avctx, AV_LOG_WARNING,
1405 "Invalid block length %u in channel data!\n",
1406 bd.block_length);
1407 continue;
1408 }
1409
1410 for (c = 0; c < avctx->channels; c++) {
1411 bd.const_block = ctx->const_block + c;
1412 bd.shift_lsbs = ctx->shift_lsbs + c;
1413 bd.opt_order = ctx->opt_order + c;
1414 bd.store_prev_samples = ctx->store_prev_samples + c;
1415 bd.use_ltp = ctx->use_ltp + c;
1416 bd.ltp_lag = ctx->ltp_lag + c;
1417 bd.ltp_gain = ctx->ltp_gain[c];
1418 bd.lpc_cof = ctx->lpc_cof[c];
1419 bd.quant_cof = ctx->quant_cof[c];
1420 bd.raw_samples = ctx->raw_samples[c] + offset;
1421 bd.raw_other = NULL;
1422
1423 if ((ret = read_block(ctx, &bd)) < 0)
1424 return ret;
1425 if ((ret = read_channel_data(ctx, ctx->chan_data[c], c)) < 0)
1426 return ret;
1427 }
1428
1429 for (c = 0; c < avctx->channels; c++) {
1430 ret = revert_channel_correlation(ctx, &bd, ctx->chan_data,
1431 reverted_channels, offset, c);
1432 if (ret < 0)
1433 return ret;
1434 }
1435 for (c = 0; c < avctx->channels; c++) {
1436 bd.const_block = ctx->const_block + c;
1437 bd.shift_lsbs = ctx->shift_lsbs + c;
1438 bd.opt_order = ctx->opt_order + c;
1439 bd.store_prev_samples = ctx->store_prev_samples + c;
1440 bd.use_ltp = ctx->use_ltp + c;
1441 bd.ltp_lag = ctx->ltp_lag + c;
1442 bd.ltp_gain = ctx->ltp_gain[c];
1443 bd.lpc_cof = ctx->lpc_cof[c];
1444 bd.quant_cof = ctx->quant_cof[c];
1445 bd.raw_samples = ctx->raw_samples[c] + offset;
1446 if ((ret = decode_block(ctx, &bd)) < 0)
1447 return ret;
1448 }
1449
1450 memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1451 offset += div_blocks[b];
1452 bd.ra_block = 0;
1453 }
1454
1455 // store carryover raw samples
1456 for (c = 0; c < avctx->channels; c++)
1457 memmove(ctx->raw_samples[c] - sconf->max_order,
1458 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1459 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1460 }
1461
1462 // TODO: read_diff_float_data
1463
1464 return 0;
1465 }
1466
1467
1468 /** Decode an ALS frame.
1469 */
1470 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr,
1471 AVPacket *avpkt)
1472 {
1473 ALSDecContext *ctx = avctx->priv_data;
1474 AVFrame *frame = data;
1475 ALSSpecificConfig *sconf = &ctx->sconf;
1476 const uint8_t *buffer = avpkt->data;
1477 int buffer_size = avpkt->size;
1478 int invalid_frame, ret;
1479 unsigned int c, sample, ra_frame, bytes_read, shift;
1480
1481 init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1482
1483 // In the case that the distance between random access frames is set to zero
1484 // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1485 // For the first frame, if prediction is used, all samples used from the
1486 // previous frame are assumed to be zero.
1487 ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1488
1489 // the last frame to decode might have a different length
1490 if (sconf->samples != 0xFFFFFFFF)
1491 ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1492 sconf->frame_length);
1493 else
1494 ctx->cur_frame_length = sconf->frame_length;
1495
1496 // decode the frame data
1497 if ((invalid_frame = read_frame_data(ctx, ra_frame)) < 0)
1498 av_log(ctx->avctx, AV_LOG_WARNING,
1499 "Reading frame data failed. Skipping RA unit.\n");
1500
1501 ctx->frame_id++;
1502
1503 /* get output buffer */
1504 frame->nb_samples = ctx->cur_frame_length;
1505 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
1506 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
1507 return ret;
1508 }
1509
1510 // transform decoded frame into output format
1511 #define INTERLEAVE_OUTPUT(bps) \
1512 { \
1513 int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \
1514 shift = bps - ctx->avctx->bits_per_raw_sample; \
1515 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1516 for (c = 0; c < avctx->channels; c++) \
1517 *dest++ = ctx->raw_samples[c][sample] << shift; \
1518 }
1519
1520 if (ctx->avctx->bits_per_raw_sample <= 16) {
1521 INTERLEAVE_OUTPUT(16)
1522 } else {
1523 INTERLEAVE_OUTPUT(32)
1524 }
1525
1526 // update CRC
1527 if (sconf->crc_enabled && (avctx->err_recognition & AV_EF_CRCCHECK)) {
1528 int swap = HAVE_BIGENDIAN != sconf->msb_first;
1529
1530 if (ctx->avctx->bits_per_raw_sample == 24) {
1531 int32_t *src = (int32_t *)frame->data[0];
1532
1533 for (sample = 0;
1534 sample < ctx->cur_frame_length * avctx->channels;
1535 sample++) {
1536 int32_t v;
1537
1538 if (swap)
1539 v = av_bswap32(src[sample]);
1540 else
1541 v = src[sample];
1542 if (!HAVE_BIGENDIAN)
1543 v >>= 8;
1544
1545 ctx->crc = av_crc(ctx->crc_table, ctx->crc, (uint8_t*)(&v), 3);
1546 }
1547 } else {
1548 uint8_t *crc_source;
1549
1550 if (swap) {
1551 if (ctx->avctx->bits_per_raw_sample <= 16) {
1552 int16_t *src = (int16_t*) frame->data[0];
1553 int16_t *dest = (int16_t*) ctx->crc_buffer;
1554 for (sample = 0;
1555 sample < ctx->cur_frame_length * avctx->channels;
1556 sample++)
1557 *dest++ = av_bswap16(src[sample]);
1558 } else {
1559 ctx->bdsp.bswap_buf((uint32_t *) ctx->crc_buffer,
1560 (uint32_t *) frame->data[0],
1561 ctx->cur_frame_length * avctx->channels);
1562 }
1563 crc_source = ctx->crc_buffer;
1564 } else {
1565 crc_source = frame->data[0];
1566 }
1567
1568 ctx->crc = av_crc(ctx->crc_table, ctx->crc, crc_source,
1569 ctx->cur_frame_length * avctx->channels *
1570 av_get_bytes_per_sample(avctx->sample_fmt));
1571 }
1572
1573
1574 // check CRC sums if this is the last frame
1575 if (ctx->cur_frame_length != sconf->frame_length &&
1576 ctx->crc_org != ctx->crc) {
1577 av_log(avctx, AV_LOG_ERROR, "CRC error.\n");
1578 if (avctx->err_recognition & AV_EF_EXPLODE)
1579 return AVERROR_INVALIDDATA;
1580 }
1581 }
1582
1583 *got_frame_ptr = 1;
1584
1585 bytes_read = invalid_frame ? buffer_size :
1586 (get_bits_count(&ctx->gb) + 7) >> 3;
1587
1588 return bytes_read;
1589 }
1590
1591
1592 /** Uninitialize the ALS decoder.
1593 */
1594 static av_cold int decode_end(AVCodecContext *avctx)
1595 {
1596 ALSDecContext *ctx = avctx->priv_data;
1597
1598 av_freep(&ctx->sconf.chan_pos);
1599
1600 ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1601
1602 av_freep(&ctx->const_block);
1603 av_freep(&ctx->shift_lsbs);
1604 av_freep(&ctx->opt_order);
1605 av_freep(&ctx->store_prev_samples);
1606 av_freep(&ctx->use_ltp);
1607 av_freep(&ctx->ltp_lag);
1608 av_freep(&ctx->ltp_gain);
1609 av_freep(&ctx->ltp_gain_buffer);
1610 av_freep(&ctx->quant_cof);
1611 av_freep(&ctx->lpc_cof);
1612 av_freep(&ctx->quant_cof_buffer);
1613 av_freep(&ctx->lpc_cof_buffer);
1614 av_freep(&ctx->lpc_cof_reversed_buffer);
1615 av_freep(&ctx->prev_raw_samples);
1616 av_freep(&ctx->raw_samples);
1617 av_freep(&ctx->raw_buffer);
1618 av_freep(&ctx->chan_data);
1619 av_freep(&ctx->chan_data_buffer);
1620 av_freep(&ctx->reverted_channels);
1621 av_freep(&ctx->crc_buffer);
1622
1623 return 0;
1624 }
1625
1626
1627 /** Initialize the ALS decoder.
1628 */
1629 static av_cold int decode_init(AVCodecContext *avctx)
1630 {
1631 unsigned int c;
1632 unsigned int channel_size;
1633 int num_buffers, ret;
1634 ALSDecContext *ctx = avctx->priv_data;
1635 ALSSpecificConfig *sconf = &ctx->sconf;
1636 ctx->avctx = avctx;
1637
1638 if (!avctx->extradata) {
1639 av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1640 return AVERROR_INVALIDDATA;
1641 }
1642
1643 if ((ret = read_specific_config(ctx)) < 0) {
1644 av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1645 goto fail;
1646 }
1647
1648 if ((ret = check_specific_config(ctx)) < 0) {
1649 goto fail;
1650 }
1651
1652 if (sconf->bgmc) {
1653 ret = ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1654 if (ret < 0)
1655 goto fail;
1656 }
1657 if (sconf->floating) {
1658 avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
1659 avctx->bits_per_raw_sample = 32;
1660 } else {
1661 avctx->sample_fmt = sconf->resolution > 1
1662 ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
1663 avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1664 if (avctx->bits_per_raw_sample > 32) {
1665 av_log(avctx, AV_LOG_ERROR, "Bits per raw sample %d larger than 32.\n",
1666 avctx->bits_per_raw_sample);
1667 ret = AVERROR_INVALIDDATA;
1668 goto fail;
1669 }
1670 }
1671
1672 // set maximum Rice parameter for progressive decoding based on resolution
1673 // This is not specified in 14496-3 but actually done by the reference
1674 // codec RM22 revision 2.
1675 ctx->s_max = sconf->resolution > 1 ? 31 : 15;
1676
1677 // set lag value for long-term prediction
1678 ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1679 (avctx->sample_rate >= 192000);
1680
1681 // allocate quantized parcor coefficient buffer
1682 num_buffers = sconf->mc_coding ? avctx->channels : 1;
1683
1684 ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1685 ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1686 ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1687 num_buffers * sconf->max_order);
1688 ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1689 num_buffers * sconf->max_order);
1690 ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1691 sconf->max_order);
1692
1693 if (!ctx->quant_cof || !ctx->lpc_cof ||
1694 !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1695 !ctx->lpc_cof_reversed_buffer) {
1696 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1697 ret = AVERROR(ENOMEM);
1698 goto fail;
1699 }
1700
1701 // assign quantized parcor coefficient buffers
1702 for (c = 0; c < num_buffers; c++) {
1703 ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1704 ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1705 }
1706
1707 // allocate and assign lag and gain data buffer for ltp mode
1708 ctx->const_block = av_malloc (sizeof(*ctx->const_block) * num_buffers);
1709 ctx->shift_lsbs = av_malloc (sizeof(*ctx->shift_lsbs) * num_buffers);
1710 ctx->opt_order = av_malloc (sizeof(*ctx->opt_order) * num_buffers);
1711 ctx->store_prev_samples = av_malloc(sizeof(*ctx->store_prev_samples) * num_buffers);
1712 ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1713 ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1714 ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1715 ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1716 num_buffers * 5);
1717
1718 if (!ctx->const_block || !ctx->shift_lsbs ||
1719 !ctx->opt_order || !ctx->store_prev_samples ||
1720 !ctx->use_ltp || !ctx->ltp_lag ||
1721 !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1722 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1723 ret = AVERROR(ENOMEM);
1724 goto fail;
1725 }
1726
1727 for (c = 0; c < num_buffers; c++)
1728 ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1729
1730 // allocate and assign channel data buffer for mcc mode
1731 if (sconf->mc_coding) {
1732 ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1733 num_buffers * num_buffers);
1734 ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) *
1735 num_buffers);
1736 ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1737 num_buffers);
1738
1739 if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1740 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1741 ret = AVERROR(ENOMEM);
1742 goto fail;
1743 }
1744
1745 for (c = 0; c < num_buffers; c++)
1746 ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
1747 } else {
1748 ctx->chan_data = NULL;
1749 ctx->chan_data_buffer = NULL;
1750 ctx->reverted_channels = NULL;
1751 }
1752
1753 channel_size = sconf->frame_length + sconf->max_order;
1754
1755 ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1756 ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1757 ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1758
1759 // allocate previous raw sample buffer
1760 if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1761 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1762 ret = AVERROR(ENOMEM);
1763 goto fail;
1764 }
1765
1766 // assign raw samples buffers
1767 ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1768 for (c = 1; c < avctx->channels; c++)
1769 ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1770
1771 // allocate crc buffer
1772 if (HAVE_BIGENDIAN != sconf->msb_first && sconf->crc_enabled &&
1773 (avctx->err_recognition & AV_EF_CRCCHECK)) {
1774 ctx->crc_buffer = av_malloc(sizeof(*ctx->crc_buffer) *
1775 ctx->cur_frame_length *
1776 avctx->channels *
1777 av_get_bytes_per_sample(avctx->sample_fmt));
1778 if (!ctx->crc_buffer) {
1779 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1780 ret = AVERROR(ENOMEM);
1781 goto fail;
1782 }
1783 }
1784
1785 ff_bswapdsp_init(&ctx->bdsp);
1786
1787 return 0;
1788
1789 fail:
1790 decode_end(avctx);
1791 return ret;
1792 }
1793
1794
1795 /** Flush (reset) the frame ID after seeking.
1796 */
1797 static av_cold void flush(AVCodecContext *avctx)
1798 {
1799 ALSDecContext *ctx = avctx->priv_data;
1800
1801 ctx->frame_id = 0;
1802 }
1803
1804
1805 AVCodec ff_als_decoder = {
1806 .name = "als",
1807 .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),
1808 .type = AVMEDIA_TYPE_AUDIO,
1809 .id = AV_CODEC_ID_MP4ALS,
1810 .priv_data_size = sizeof(ALSDecContext),
1811 .init = decode_init,
1812 .close = decode_end,
1813 .decode = decode_frame,
1814 .flush = flush,
1815 .capabilities = AV_CODEC_CAP_SUBFRAMES | AV_CODEC_CAP_DR1,
1816 };