3 * Copyright (c) 2009 Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
5 * This file is part of FFmpeg.
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.
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.
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
23 * @file libavcodec/alsdec.c
25 * @author Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
35 #include "mpeg4audio.h"
36 #include "bytestream.h"
40 /** Rice parameters and corresponding index offsets for decoding the
41 * indices of scaled PARCOR values. The table choosen is set globally
42 * by the encoder and stored in ALSSpecificConfig.
44 static const int8_t parcor_rice_table[3][20][2] = {
45 { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
46 { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
47 { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
48 { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
49 { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
50 { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
51 {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
52 { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
53 { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
54 { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
55 {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
56 { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
60 /** Scaled PARCOR values used for the first two PARCOR coefficients.
61 * To be indexed by the Rice coded indices.
62 * Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20)
63 * Actual values are divided by 32 in order to be stored in 16 bits.
65 static const int16_t parcor_scaled_values[] = {
66 -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
67 -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
68 -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
69 -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
70 -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
71 -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
72 -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
73 -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
74 -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
75 -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
76 -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
77 -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
78 -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
79 -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
80 -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
81 -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
82 -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
83 -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
84 -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
85 -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
86 -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
87 -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
88 -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
89 46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
90 143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
91 244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
92 349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
93 458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
94 571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
95 688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
96 810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
97 935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
101 /** Gain values of p(0) for long-term prediction.
102 * To be indexed by the Rice coded indices.
104 static const uint8_t ltp_gain_values [4][4] = {
112 /** Inter-channel weighting factors for multi-channel correlation.
113 * To be indexed by the Rice coded indices.
115 static const int16_t mcc_weightings[] = {
116 204, 192, 179, 166, 153, 140, 128, 115,
117 102, 89, 76, 64, 51, 38, 25, 12,
118 0, -12, -25, -38, -51, -64, -76, -89,
119 -102, -115, -128, -140, -153, -166, -179, -192
131 uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown
132 int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
133 int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer
134 int frame_length; ///< frame length for each frame (last frame may differ)
135 int ra_distance; ///< distance between RA frames (in frames, 0...255)
136 enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored
137 int adapt_order; ///< adaptive order: 1 = on, 0 = off
138 int coef_table; ///< table index of Rice code parameters
139 int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off
140 int max_order; ///< maximum prediction order (0..1023)
141 int block_switching; ///< number of block switching levels
142 int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
143 int sb_part; ///< sub-block partition
144 int joint_stereo; ///< joint stereo: 1 = on, 0 = off
145 int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off
146 int chan_config; ///< indicates that a chan_config_info field is present
147 int chan_sort; ///< channel rearrangement: 1 = on, 0 = off
148 int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
149 int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented.
150 int *chan_pos; ///< original channel positions
151 uint32_t header_size; ///< header size of original audio file in bytes, provided for debugging
152 uint32_t trailer_size; ///< trailer size of original audio file in bytes, provided for debugging
167 AVCodecContext *avctx;
168 ALSSpecificConfig sconf;
170 unsigned int cur_frame_length; ///< length of the current frame to decode
171 unsigned int frame_id; ///< the frame ID / number of the current frame
172 unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
173 unsigned int num_blocks; ///< number of blocks used in the current frame
174 int ltp_lag_length; ///< number of bits used for ltp lag value
175 int *use_ltp; ///< contains use_ltp flags for all channels
176 int *ltp_lag; ///< contains ltp lag values for all channels
177 int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
178 int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
179 int32_t **quant_cof; ///< quantized parcor coefficients for a channel
180 int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
181 int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
182 int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
183 int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
184 ALSChannelData **chan_data; ///< channel data for multi-channel correlation
185 ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
186 int *reverted_channels; ///< stores a flag for each reverted channel
187 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
188 int32_t **raw_samples; ///< decoded raw samples for each channel
189 int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
194 unsigned int block_length; ///< number of samples within the block
195 unsigned int ra_block; ///< if true, this is a random access block
196 int const_block; ///< if true, this is a constant value block
197 int32_t const_val; ///< the sample value of a constant block
198 int js_blocks; ///< true if this block contains a difference signal
199 unsigned int shift_lsbs; ///< shift of values for this block
200 unsigned int opt_order; ///< prediction order of this block
201 int store_prev_samples;///< if true, carryover samples have to be stored
202 int *use_ltp; ///< if true, long-term prediction is used
203 int *ltp_lag; ///< lag value for long-term prediction
204 int *ltp_gain; ///< gain values for ltp 5-tap filter
205 int32_t *quant_cof; ///< quantized parcor coefficients
206 int32_t *lpc_cof; ///< coefficients of the direct form prediction
207 int32_t *raw_samples; ///< decoded raw samples / residuals for this block
208 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
209 int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
213 static av_cold void dprint_specific_config(ALSDecContext *ctx)
216 AVCodecContext *avctx = ctx->avctx;
217 ALSSpecificConfig *sconf = &ctx->sconf;
219 dprintf(avctx, "resolution = %i\n", sconf->resolution);
220 dprintf(avctx, "floating = %i\n", sconf->floating);
221 dprintf(avctx, "frame_length = %i\n", sconf->frame_length);
222 dprintf(avctx, "ra_distance = %i\n", sconf->ra_distance);
223 dprintf(avctx, "ra_flag = %i\n", sconf->ra_flag);
224 dprintf(avctx, "adapt_order = %i\n", sconf->adapt_order);
225 dprintf(avctx, "coef_table = %i\n", sconf->coef_table);
226 dprintf(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
227 dprintf(avctx, "max_order = %i\n", sconf->max_order);
228 dprintf(avctx, "block_switching = %i\n", sconf->block_switching);
229 dprintf(avctx, "bgmc = %i\n", sconf->bgmc);
230 dprintf(avctx, "sb_part = %i\n", sconf->sb_part);
231 dprintf(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
232 dprintf(avctx, "mc_coding = %i\n", sconf->mc_coding);
233 dprintf(avctx, "chan_config = %i\n", sconf->chan_config);
234 dprintf(avctx, "chan_sort = %i\n", sconf->chan_sort);
235 dprintf(avctx, "RLSLMS = %i\n", sconf->rlslms);
236 dprintf(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
237 dprintf(avctx, "header_size = %i\n", sconf->header_size);
238 dprintf(avctx, "trailer_size = %i\n", sconf->trailer_size);
243 /** Reads an ALSSpecificConfig from a buffer into the output struct.
245 static av_cold int read_specific_config(ALSDecContext *ctx)
249 int i, config_offset, crc_enabled;
250 MPEG4AudioConfig m4ac;
251 ALSSpecificConfig *sconf = &ctx->sconf;
252 AVCodecContext *avctx = ctx->avctx;
255 init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
257 config_offset = ff_mpeg4audio_get_config(&m4ac, avctx->extradata,
258 avctx->extradata_size);
260 if (config_offset < 0)
263 skip_bits_long(&gb, config_offset);
265 if (get_bits_left(&gb) < (30 << 3))
268 // read the fixed items
269 als_id = get_bits_long(&gb, 32);
270 avctx->sample_rate = m4ac.sample_rate;
271 skip_bits_long(&gb, 32); // sample rate already known
272 sconf->samples = get_bits_long(&gb, 32);
273 avctx->channels = m4ac.channels;
274 skip_bits(&gb, 16); // number of channels already knwon
275 skip_bits(&gb, 3); // skip file_type
276 sconf->resolution = get_bits(&gb, 3);
277 sconf->floating = get_bits1(&gb);
278 skip_bits1(&gb); // skip msb_first
279 sconf->frame_length = get_bits(&gb, 16) + 1;
280 sconf->ra_distance = get_bits(&gb, 8);
281 sconf->ra_flag = get_bits(&gb, 2);
282 sconf->adapt_order = get_bits1(&gb);
283 sconf->coef_table = get_bits(&gb, 2);
284 sconf->long_term_prediction = get_bits1(&gb);
285 sconf->max_order = get_bits(&gb, 10);
286 sconf->block_switching = get_bits(&gb, 2);
287 sconf->bgmc = get_bits1(&gb);
288 sconf->sb_part = get_bits1(&gb);
289 sconf->joint_stereo = get_bits1(&gb);
290 sconf->mc_coding = get_bits1(&gb);
291 sconf->chan_config = get_bits1(&gb);
292 sconf->chan_sort = get_bits1(&gb);
293 crc_enabled = get_bits1(&gb);
294 sconf->rlslms = get_bits1(&gb);
295 skip_bits(&gb, 5); // skip 5 reserved bits
296 skip_bits1(&gb); // skip aux_data_enabled
299 // check for ALSSpecificConfig struct
300 if (als_id != MKBETAG('A','L','S','\0'))
303 ctx->cur_frame_length = sconf->frame_length;
305 // read channel config
306 if (sconf->chan_config)
307 sconf->chan_config_info = get_bits(&gb, 16);
308 // TODO: use this to set avctx->channel_layout
311 // read channel sorting
312 if (sconf->chan_sort && avctx->channels > 1) {
313 int chan_pos_bits = av_ceil_log2(avctx->channels);
314 int bits_needed = avctx->channels * chan_pos_bits + 7;
315 if (get_bits_left(&gb) < bits_needed)
318 if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
319 return AVERROR(ENOMEM);
321 for (i = 0; i < avctx->channels; i++)
322 sconf->chan_pos[i] = get_bits(&gb, chan_pos_bits);
325 // TODO: use this to actually do channel sorting
327 sconf->chan_sort = 0;
331 // read fixed header and trailer sizes,
332 // if size = 0xFFFFFFFF then there is no data field!
333 if (get_bits_left(&gb) < 64)
336 sconf->header_size = get_bits_long(&gb, 32);
337 sconf->trailer_size = get_bits_long(&gb, 32);
338 if (sconf->header_size == 0xFFFFFFFF)
339 sconf->header_size = 0;
340 if (sconf->trailer_size == 0xFFFFFFFF)
341 sconf->trailer_size = 0;
343 ht_size = ((int64_t)(sconf->header_size) + (int64_t)(sconf->trailer_size)) << 3;
346 // skip the header and trailer data
347 if (get_bits_left(&gb) < ht_size)
350 if (ht_size > INT32_MAX)
353 skip_bits_long(&gb, ht_size);
358 if (get_bits_left(&gb) < 32)
361 skip_bits_long(&gb, 32);
365 // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
367 dprint_specific_config(ctx);
373 /** Checks the ALSSpecificConfig for unsupported features.
375 static int check_specific_config(ALSDecContext *ctx)
377 ALSSpecificConfig *sconf = &ctx->sconf;
380 // report unsupported feature and set error value
381 #define MISSING_ERR(cond, str, errval) \
384 av_log_missing_feature(ctx->avctx, str, 0); \
389 MISSING_ERR(sconf->floating, "Floating point decoding", -1);
390 MISSING_ERR(sconf->bgmc, "BGMC entropy decoding", -1);
391 MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", -1);
392 MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
398 /** Parses the bs_info field to extract the block partitioning used in
399 * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
401 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
402 unsigned int div, unsigned int **div_blocks,
403 unsigned int *num_blocks)
405 if (n < 31 && ((bs_info << n) & 0x40000000)) {
406 // if the level is valid and the investigated bit n is set
407 // then recursively check both children at bits (2n+1) and (2n+2)
410 parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
411 parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
413 // else the bit is not set or the last level has been reached
414 // (bit implicitly not set)
422 /** Reads and decodes a Rice codeword.
424 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
426 int max = get_bits_left(gb) - k;
427 int q = get_unary(gb, 0, max);
428 int r = k ? get_bits1(gb) : !(q & 1);
432 q += get_bits_long(gb, k - 1);
440 /** Converts PARCOR coefficient k to direct filter coefficient.
442 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
446 for (i = 0, j = k - 1; i < j; i++, j--) {
447 int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
448 cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
452 cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
458 /** Reads block switching field if necessary and sets actual block sizes.
459 * Also assures that the block sizes of the last frame correspond to the
460 * actual number of samples.
462 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
465 ALSSpecificConfig *sconf = &ctx->sconf;
466 GetBitContext *gb = &ctx->gb;
467 unsigned int *ptr_div_blocks = div_blocks;
470 if (sconf->block_switching) {
471 unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
472 *bs_info = get_bits_long(gb, bs_info_len);
473 *bs_info <<= (32 - bs_info_len);
477 parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
479 // The last frame may have an overdetermined block structure given in
480 // the bitstream. In that case the defined block structure would need
481 // more samples than available to be consistent.
482 // The block structure is actually used but the block sizes are adapted
483 // to fit the actual number of available samples.
484 // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
485 // This results in the actual block sizes: 2 2 1 0.
486 // This is not specified in 14496-3 but actually done by the reference
487 // codec RM22 revision 2.
488 // This appears to happen in case of an odd number of samples in the last
489 // frame which is actually not allowed by the block length switching part
491 // The ALS conformance files feature an odd number of samples in the last
494 for (b = 0; b < ctx->num_blocks; b++)
495 div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
497 if (ctx->cur_frame_length != ctx->sconf.frame_length) {
498 unsigned int remaining = ctx->cur_frame_length;
500 for (b = 0; b < ctx->num_blocks; b++) {
501 if (remaining < div_blocks[b]) {
502 div_blocks[b] = remaining;
503 ctx->num_blocks = b + 1;
507 remaining -= div_blocks[b];
513 /** Reads the block data for a constant block
515 static void read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
517 ALSSpecificConfig *sconf = &ctx->sconf;
518 AVCodecContext *avctx = ctx->avctx;
519 GetBitContext *gb = &ctx->gb;
522 bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
523 bd->js_blocks = get_bits1(gb);
525 // skip 5 reserved bits
528 if (bd->const_block) {
529 unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
530 bd->const_val = get_sbits_long(gb, const_val_bits);
533 // ensure constant block decoding by reusing this field
538 /** Decodes the block data for a constant block
540 static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
542 int smp = bd->block_length;
543 int32_t val = bd->const_val;
544 int32_t *dst = bd->raw_samples;
546 // write raw samples into buffer
552 /** Reads the block data for a non-constant block
554 static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
556 ALSSpecificConfig *sconf = &ctx->sconf;
557 AVCodecContext *avctx = ctx->avctx;
558 GetBitContext *gb = &ctx->gb;
561 unsigned int sub_blocks, log2_sub_blocks, sb_length;
562 unsigned int start = 0;
563 unsigned int opt_order;
565 int32_t *quant_cof = bd->quant_cof;
568 // ensure variable block decoding by reusing this field
572 bd->js_blocks = get_bits1(gb);
574 opt_order = bd->opt_order;
576 // determine the number of subblocks for entropy decoding
577 if (!sconf->bgmc && !sconf->sb_part) {
580 if (sconf->bgmc && sconf->sb_part)
581 log2_sub_blocks = get_bits(gb, 2);
583 log2_sub_blocks = 2 * get_bits1(gb);
586 sub_blocks = 1 << log2_sub_blocks;
588 // do not continue in case of a damaged stream since
589 // block_length must be evenly divisible by sub_blocks
590 if (bd->block_length & (sub_blocks - 1)) {
591 av_log(avctx, AV_LOG_WARNING,
592 "Block length is not evenly divisible by the number of subblocks.\n");
596 sb_length = bd->block_length >> log2_sub_blocks;
602 s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
603 for (k = 1; k < sub_blocks; k++)
604 s[k] = s[k - 1] + decode_rice(gb, 0);
608 bd->shift_lsbs = get_bits(gb, 4) + 1;
610 bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || bd->shift_lsbs;
613 if (!sconf->rlslms) {
614 if (sconf->adapt_order) {
615 int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
616 2, sconf->max_order + 1));
617 bd->opt_order = get_bits(gb, opt_order_length);
619 bd->opt_order = sconf->max_order;
622 opt_order = bd->opt_order;
627 if (sconf->coef_table == 3) {
630 // read coefficient 0
631 quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
633 // read coefficient 1
635 quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
637 // read coefficients 2 to opt_order
638 for (k = 2; k < opt_order; k++)
639 quant_cof[k] = get_bits(gb, 7);
644 // read coefficient 0 to 19
645 k_max = FFMIN(opt_order, 20);
646 for (k = 0; k < k_max; k++) {
647 int rice_param = parcor_rice_table[sconf->coef_table][k][1];
648 int offset = parcor_rice_table[sconf->coef_table][k][0];
649 quant_cof[k] = decode_rice(gb, rice_param) + offset;
652 // read coefficients 20 to 126
653 k_max = FFMIN(opt_order, 127);
654 for (; k < k_max; k++)
655 quant_cof[k] = decode_rice(gb, 2) + (k & 1);
657 // read coefficients 127 to opt_order
658 for (; k < opt_order; k++)
659 quant_cof[k] = decode_rice(gb, 1);
661 quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
664 quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
667 for (k = 2; k < opt_order; k++)
668 quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
672 // read LTP gain and lag values
673 if (sconf->long_term_prediction) {
674 *bd->use_ltp = get_bits1(gb);
677 bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
678 bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
680 bd->ltp_gain[2] = ltp_gain_values[get_unary(gb, 0, 4)][get_bits(gb, 2)];
682 bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
683 bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
685 *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
686 *bd->ltp_lag += FFMAX(4, opt_order + 1);
690 // read first value and residuals in case of a random access block
693 bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
695 bd->raw_samples[1] = decode_rice(gb, s[0] + 3);
697 bd->raw_samples[2] = decode_rice(gb, s[0] + 1);
699 start = FFMIN(opt_order, 3);
702 // read all residuals
706 int32_t *current_res = bd->raw_samples + start;
708 for (sb = 0; sb < sub_blocks; sb++, start = 0)
709 for (; start < sb_length; start++)
710 *current_res++ = decode_rice(gb, s[sb]);
713 if (!sconf->mc_coding || ctx->js_switch)
720 /** Decodes the block data for a non-constant block
722 static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
724 ALSSpecificConfig *sconf = &ctx->sconf;
725 unsigned int block_length = bd->block_length;
726 unsigned int smp = 0;
728 int opt_order = bd->opt_order;
731 int32_t *quant_cof = bd->quant_cof;
732 int32_t *lpc_cof = bd->lpc_cof;
733 int32_t *raw_samples = bd->raw_samples;
734 int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
735 int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
737 // reverse long-term prediction
741 for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
742 int center = ltp_smp - *bd->ltp_lag;
743 int begin = FFMAX(0, center - 2);
744 int end = center + 3;
745 int tab = 5 - (end - begin);
750 for (base = begin; base < end; base++, tab++)
751 y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
753 raw_samples[ltp_smp] += y >> 7;
757 // reconstruct all samples from residuals
759 for (smp = 0; smp < opt_order; smp++) {
762 for (sb = 0; sb < smp; sb++)
763 y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
765 *raw_samples++ -= y >> 20;
766 parcor_to_lpc(smp, quant_cof, lpc_cof);
769 for (k = 0; k < opt_order; k++)
770 parcor_to_lpc(k, quant_cof, lpc_cof);
772 // store previous samples in case that they have to be altered
773 if (bd->store_prev_samples)
774 memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
775 sizeof(*bd->prev_raw_samples) * sconf->max_order);
777 // reconstruct difference signal for prediction (joint-stereo)
778 if (bd->js_blocks && bd->raw_other) {
779 int32_t *left, *right;
781 if (bd->raw_other > raw_samples) { // D = R - L
783 right = bd->raw_other;
784 } else { // D = R - L
785 left = bd->raw_other;
789 for (sb = -1; sb >= -sconf->max_order; sb--)
790 raw_samples[sb] = right[sb] - left[sb];
793 // reconstruct shifted signal
795 for (sb = -1; sb >= -sconf->max_order; sb--)
796 raw_samples[sb] >>= bd->shift_lsbs;
799 // reverse linear prediction coefficients for efficiency
800 lpc_cof = lpc_cof + opt_order;
802 for (sb = 0; sb < opt_order; sb++)
803 lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
805 // reconstruct raw samples
806 raw_samples = bd->raw_samples + smp;
807 lpc_cof = lpc_cof_reversed + opt_order;
809 for (; raw_samples < raw_samples_end; raw_samples++) {
812 for (sb = -opt_order; sb < 0; sb++)
813 y += MUL64(lpc_cof[sb], raw_samples[sb]);
815 *raw_samples -= y >> 20;
818 raw_samples = bd->raw_samples;
820 // restore previous samples in case that they have been altered
821 if (bd->store_prev_samples)
822 memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
823 sizeof(*raw_samples) * sconf->max_order);
829 /** Reads the block data.
831 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
833 GetBitContext *gb = &ctx->gb;
835 // read block type flag and read the samples accordingly
837 if (read_var_block_data(ctx, bd))
840 read_const_block_data(ctx, bd);
847 /** Decodes the block data.
849 static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
853 // read block type flag and read the samples accordingly
855 decode_const_block_data(ctx, bd);
856 else if (decode_var_block_data(ctx, bd))
859 // TODO: read RLSLMS extension data
862 for (smp = 0; smp < bd->block_length; smp++)
863 bd->raw_samples[smp] <<= bd->shift_lsbs;
869 /** Reads and decodes block data successively.
871 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
875 ret = read_block(ctx, bd);
880 ret = decode_block(ctx, bd);
886 /** Computes the number of samples left to decode for the current frame and
887 * sets these samples to zero.
889 static void zero_remaining(unsigned int b, unsigned int b_max,
890 const unsigned int *div_blocks, int32_t *buf)
892 unsigned int count = 0;
895 count += div_blocks[b];
898 memset(buf, 0, sizeof(*buf) * count);
902 /** Decodes blocks independently.
904 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
905 unsigned int c, const unsigned int *div_blocks,
906 unsigned int *js_blocks)
911 memset(&bd, 0, sizeof(ALSBlockData));
913 bd.ra_block = ra_frame;
914 bd.use_ltp = ctx->use_ltp;
915 bd.ltp_lag = ctx->ltp_lag;
916 bd.ltp_gain = ctx->ltp_gain[0];
917 bd.quant_cof = ctx->quant_cof[0];
918 bd.lpc_cof = ctx->lpc_cof[0];
919 bd.prev_raw_samples = ctx->prev_raw_samples;
920 bd.raw_samples = ctx->raw_samples[c];
923 for (b = 0; b < ctx->num_blocks; b++) {
925 bd.block_length = div_blocks[b];
927 if (read_decode_block(ctx, &bd)) {
928 // damaged block, write zero for the rest of the frame
929 zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
932 bd.raw_samples += div_blocks[b];
940 /** Decodes blocks dependently.
942 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
943 unsigned int c, const unsigned int *div_blocks,
944 unsigned int *js_blocks)
946 ALSSpecificConfig *sconf = &ctx->sconf;
947 unsigned int offset = 0;
951 memset(bd, 0, 2 * sizeof(ALSBlockData));
953 bd[0].ra_block = ra_frame;
954 bd[0].use_ltp = ctx->use_ltp;
955 bd[0].ltp_lag = ctx->ltp_lag;
956 bd[0].ltp_gain = ctx->ltp_gain[0];
957 bd[0].quant_cof = ctx->quant_cof[0];
958 bd[0].lpc_cof = ctx->lpc_cof[0];
959 bd[0].prev_raw_samples = ctx->prev_raw_samples;
960 bd[0].js_blocks = *js_blocks;
962 bd[1].ra_block = ra_frame;
963 bd[1].use_ltp = ctx->use_ltp;
964 bd[1].ltp_lag = ctx->ltp_lag;
965 bd[1].ltp_gain = ctx->ltp_gain[0];
966 bd[1].quant_cof = ctx->quant_cof[0];
967 bd[1].lpc_cof = ctx->lpc_cof[0];
968 bd[1].prev_raw_samples = ctx->prev_raw_samples;
969 bd[1].js_blocks = *(js_blocks + 1);
972 for (b = 0; b < ctx->num_blocks; b++) {
975 bd[0].shift_lsbs = 0;
976 bd[1].shift_lsbs = 0;
978 bd[0].block_length = div_blocks[b];
979 bd[1].block_length = div_blocks[b];
981 bd[0].raw_samples = ctx->raw_samples[c ] + offset;
982 bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
984 bd[0].raw_other = bd[1].raw_samples;
985 bd[1].raw_other = bd[0].raw_samples;
987 if(read_decode_block(ctx, &bd[0]) || read_decode_block(ctx, &bd[1])) {
988 // damaged block, write zero for the rest of the frame
989 zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
990 zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
994 // reconstruct joint-stereo blocks
995 if (bd[0].js_blocks) {
997 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair!\n");
999 for (s = 0; s < div_blocks[b]; s++)
1000 bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1001 } else if (bd[1].js_blocks) {
1002 for (s = 0; s < div_blocks[b]; s++)
1003 bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1006 offset += div_blocks[b];
1011 // store carryover raw samples,
1012 // the others channel raw samples are stored by the calling function.
1013 memmove(ctx->raw_samples[c] - sconf->max_order,
1014 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1015 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1021 /** Reads the channel data.
1023 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1025 GetBitContext *gb = &ctx->gb;
1026 ALSChannelData *current = cd;
1027 unsigned int channels = ctx->avctx->channels;
1030 while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1031 current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1033 if (current->master_channel >= channels) {
1034 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel!\n");
1038 if (current->master_channel != c) {
1039 current->time_diff_flag = get_bits1(gb);
1040 current->weighting[0] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1041 current->weighting[1] = mcc_weightings[av_clip(decode_rice(gb, 2) + 14, 0, 32)];
1042 current->weighting[2] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1044 if (current->time_diff_flag) {
1045 current->weighting[3] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1046 current->weighting[4] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1047 current->weighting[5] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1049 current->time_diff_sign = get_bits1(gb);
1050 current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1058 if (entries == channels) {
1059 av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data!\n");
1068 /** Recursively reverts the inter-channel correlation for a block.
1070 static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1071 ALSChannelData **cd, int *reverted,
1072 unsigned int offset, int c)
1074 ALSChannelData *ch = cd[c];
1075 unsigned int dep = 0;
1076 unsigned int channels = ctx->avctx->channels;
1083 while (dep < channels && !ch[dep].stop_flag) {
1084 revert_channel_correlation(ctx, bd, cd, reverted, offset,
1085 ch[dep].master_channel);
1090 if (dep == channels) {
1091 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation!\n");
1095 bd->use_ltp = ctx->use_ltp + c;
1096 bd->ltp_lag = ctx->ltp_lag + c;
1097 bd->ltp_gain = ctx->ltp_gain[c];
1098 bd->lpc_cof = ctx->lpc_cof[c];
1099 bd->quant_cof = ctx->quant_cof[c];
1100 bd->raw_samples = ctx->raw_samples[c] + offset;
1103 while (!ch[dep].stop_flag) {
1105 unsigned int begin = 1;
1106 unsigned int end = bd->block_length - 1;
1108 int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1110 if (ch[dep].time_diff_flag) {
1111 int t = ch[dep].time_diff_index;
1113 if (ch[dep].time_diff_sign) {
1120 for (smp = begin; smp < end; smp++) {
1122 MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1123 MUL64(ch[dep].weighting[1], master[smp ]) +
1124 MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1125 MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1126 MUL64(ch[dep].weighting[4], master[smp + t]) +
1127 MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1129 bd->raw_samples[smp] += y >> 7;
1132 for (smp = begin; smp < end; smp++) {
1134 MUL64(ch[dep].weighting[0], master[smp - 1]) +
1135 MUL64(ch[dep].weighting[1], master[smp ]) +
1136 MUL64(ch[dep].weighting[2], master[smp + 1]);
1138 bd->raw_samples[smp] += y >> 7;
1149 /** Reads the frame data.
1151 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1153 ALSSpecificConfig *sconf = &ctx->sconf;
1154 AVCodecContext *avctx = ctx->avctx;
1155 GetBitContext *gb = &ctx->gb;
1156 unsigned int div_blocks[32]; ///< block sizes.
1158 unsigned int js_blocks[2];
1160 uint32_t bs_info = 0;
1162 // skip the size of the ra unit if present in the frame
1163 if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1164 skip_bits_long(gb, 32);
1166 if (sconf->mc_coding && sconf->joint_stereo) {
1167 ctx->js_switch = get_bits1(gb);
1171 if (!sconf->mc_coding || ctx->js_switch) {
1172 int independent_bs = !sconf->joint_stereo;
1174 for (c = 0; c < avctx->channels; c++) {
1178 get_block_sizes(ctx, div_blocks, &bs_info);
1180 // if joint_stereo and block_switching is set, independent decoding
1181 // is signaled via the first bit of bs_info
1182 if (sconf->joint_stereo && sconf->block_switching)
1186 // if this is the last channel, it has to be decoded independently
1187 if (c == avctx->channels - 1)
1190 if (independent_bs) {
1191 if (decode_blocks_ind(ctx, ra_frame, c, div_blocks, js_blocks))
1196 if (decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks))
1202 // store carryover raw samples
1203 memmove(ctx->raw_samples[c] - sconf->max_order,
1204 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1205 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1207 } else { // multi-channel coding
1210 int *reverted_channels = ctx->reverted_channels;
1211 unsigned int offset = 0;
1213 for (c = 0; c < avctx->channels; c++)
1214 if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1215 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data!\n");
1219 memset(&bd, 0, sizeof(ALSBlockData));
1220 memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1222 bd.ra_block = ra_frame;
1223 bd.prev_raw_samples = ctx->prev_raw_samples;
1225 get_block_sizes(ctx, div_blocks, &bs_info);
1227 for (b = 0; b < ctx->num_blocks; b++) {
1229 bd.block_length = div_blocks[b];
1231 for (c = 0; c < avctx->channels; c++) {
1232 bd.use_ltp = ctx->use_ltp + c;
1233 bd.ltp_lag = ctx->ltp_lag + c;
1234 bd.ltp_gain = ctx->ltp_gain[c];
1235 bd.lpc_cof = ctx->lpc_cof[c];
1236 bd.quant_cof = ctx->quant_cof[c];
1237 bd.raw_samples = ctx->raw_samples[c] + offset;
1238 bd.raw_other = NULL;
1240 read_block(ctx, &bd);
1241 if (read_channel_data(ctx, ctx->chan_data[c], c))
1245 for (c = 0; c < avctx->channels; c++)
1246 if (revert_channel_correlation(ctx, &bd, ctx->chan_data,
1247 reverted_channels, offset, c))
1250 for (c = 0; c < avctx->channels; c++) {
1251 bd.use_ltp = ctx->use_ltp + c;
1252 bd.ltp_lag = ctx->ltp_lag + c;
1253 bd.ltp_gain = ctx->ltp_gain[c];
1254 bd.lpc_cof = ctx->lpc_cof[c];
1255 bd.quant_cof = ctx->quant_cof[c];
1256 bd.raw_samples = ctx->raw_samples[c] + offset;
1257 decode_block(ctx, &bd);
1260 memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1261 offset += div_blocks[b];
1265 // store carryover raw samples
1266 for (c = 0; c < avctx->channels; c++)
1267 memmove(ctx->raw_samples[c] - sconf->max_order,
1268 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1269 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1272 // TODO: read_diff_float_data
1278 /** Decodes an ALS frame.
1280 static int decode_frame(AVCodecContext *avctx,
1281 void *data, int *data_size,
1284 ALSDecContext *ctx = avctx->priv_data;
1285 ALSSpecificConfig *sconf = &ctx->sconf;
1286 const uint8_t *buffer = avpkt->data;
1287 int buffer_size = avpkt->size;
1288 int invalid_frame, size;
1289 unsigned int c, sample, ra_frame, bytes_read, shift;
1291 init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1293 // In the case that the distance between random access frames is set to zero
1294 // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1295 // For the first frame, if prediction is used, all samples used from the
1296 // previous frame are assumed to be zero.
1297 ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1299 // the last frame to decode might have a different length
1300 if (sconf->samples != 0xFFFFFFFF)
1301 ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1302 sconf->frame_length);
1304 ctx->cur_frame_length = sconf->frame_length;
1306 // decode the frame data
1307 if ((invalid_frame = read_frame_data(ctx, ra_frame) < 0))
1308 av_log(ctx->avctx, AV_LOG_WARNING,
1309 "Reading frame data failed. Skipping RA unit.\n");
1313 // check for size of decoded data
1314 size = ctx->cur_frame_length * avctx->channels *
1315 (av_get_bits_per_sample_format(avctx->sample_fmt) >> 3);
1317 if (size > *data_size) {
1318 av_log(avctx, AV_LOG_ERROR, "Decoded data exceeds buffer size.\n");
1324 // transform decoded frame into output format
1325 #define INTERLEAVE_OUTPUT(bps) \
1327 int##bps##_t *dest = (int##bps##_t*) data; \
1328 shift = bps - ctx->avctx->bits_per_raw_sample; \
1329 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1330 for (c = 0; c < avctx->channels; c++) \
1331 *dest++ = ctx->raw_samples[c][sample] << shift; \
1334 if (ctx->avctx->bits_per_raw_sample <= 16) {
1335 INTERLEAVE_OUTPUT(16)
1337 INTERLEAVE_OUTPUT(32)
1340 bytes_read = invalid_frame ? buffer_size :
1341 (get_bits_count(&ctx->gb) + 7) >> 3;
1347 /** Uninitializes the ALS decoder.
1349 static av_cold int decode_end(AVCodecContext *avctx)
1351 ALSDecContext *ctx = avctx->priv_data;
1353 av_freep(&ctx->sconf.chan_pos);
1355 av_freep(&ctx->use_ltp);
1356 av_freep(&ctx->ltp_lag);
1357 av_freep(&ctx->ltp_gain);
1358 av_freep(&ctx->ltp_gain_buffer);
1359 av_freep(&ctx->quant_cof);
1360 av_freep(&ctx->lpc_cof);
1361 av_freep(&ctx->quant_cof_buffer);
1362 av_freep(&ctx->lpc_cof_buffer);
1363 av_freep(&ctx->lpc_cof_reversed_buffer);
1364 av_freep(&ctx->prev_raw_samples);
1365 av_freep(&ctx->raw_samples);
1366 av_freep(&ctx->raw_buffer);
1367 av_freep(&ctx->chan_data);
1368 av_freep(&ctx->chan_data_buffer);
1369 av_freep(&ctx->reverted_channels);
1375 /** Initializes the ALS decoder.
1377 static av_cold int decode_init(AVCodecContext *avctx)
1380 unsigned int channel_size;
1382 ALSDecContext *ctx = avctx->priv_data;
1383 ALSSpecificConfig *sconf = &ctx->sconf;
1386 if (!avctx->extradata) {
1387 av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1391 if (read_specific_config(ctx)) {
1392 av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1397 if (check_specific_config(ctx)) {
1402 if (sconf->floating) {
1403 avctx->sample_fmt = SAMPLE_FMT_FLT;
1404 avctx->bits_per_raw_sample = 32;
1406 avctx->sample_fmt = sconf->resolution > 1
1407 ? SAMPLE_FMT_S32 : SAMPLE_FMT_S16;
1408 avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1411 // set lag value for long-term prediction
1412 ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1413 (avctx->sample_rate >= 192000);
1415 // allocate quantized parcor coefficient buffer
1416 num_buffers = sconf->mc_coding ? avctx->channels : 1;
1418 ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1419 ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1420 ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1421 num_buffers * sconf->max_order);
1422 ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1423 num_buffers * sconf->max_order);
1424 ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1427 if (!ctx->quant_cof || !ctx->lpc_cof ||
1428 !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1429 !ctx->lpc_cof_reversed_buffer) {
1430 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1431 return AVERROR(ENOMEM);
1434 // assign quantized parcor coefficient buffers
1435 for (c = 0; c < num_buffers; c++) {
1436 ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1437 ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1440 // allocate and assign lag and gain data buffer for ltp mode
1441 ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1442 ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1443 ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1444 ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1447 if (!ctx->use_ltp || !ctx->ltp_lag ||
1448 !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1449 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1451 return AVERROR(ENOMEM);
1454 for (c = 0; c < num_buffers; c++)
1455 ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1457 // allocate and assign channel data buffer for mcc mode
1458 if (sconf->mc_coding) {
1459 ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1461 ctx->chan_data = av_malloc(sizeof(ALSChannelData) *
1463 ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1466 if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1467 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1469 return AVERROR(ENOMEM);
1472 for (c = 0; c < num_buffers; c++)
1473 ctx->chan_data[c] = ctx->chan_data_buffer + c;
1475 ctx->chan_data = NULL;
1476 ctx->chan_data_buffer = NULL;
1477 ctx->reverted_channels = NULL;
1480 avctx->frame_size = sconf->frame_length;
1481 channel_size = sconf->frame_length + sconf->max_order;
1483 ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1484 ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1485 ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1487 // allocate previous raw sample buffer
1488 if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1489 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1491 return AVERROR(ENOMEM);
1494 // assign raw samples buffers
1495 ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1496 for (c = 1; c < avctx->channels; c++)
1497 ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1503 /** Flushes (resets) the frame ID after seeking.
1505 static av_cold void flush(AVCodecContext *avctx)
1507 ALSDecContext *ctx = avctx->priv_data;
1513 AVCodec als_decoder = {
1517 sizeof(ALSDecContext),
1523 .capabilities = CODEC_CAP_SUBFRAMES,
1524 .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),