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"
41 /** Rice parameters and corresponding index offsets for decoding the
42 * indices of scaled PARCOR values. The table choosen is set globally
43 * by the encoder and stored in ALSSpecificConfig.
45 static const int8_t parcor_rice_table[3][20][2] = {
46 { {-52, 4}, {-29, 5}, {-31, 4}, { 19, 4}, {-16, 4},
47 { 12, 3}, { -7, 3}, { 9, 3}, { -5, 3}, { 6, 3},
48 { -4, 3}, { 3, 3}, { -3, 2}, { 3, 2}, { -2, 2},
49 { 3, 2}, { -1, 2}, { 2, 2}, { -1, 2}, { 2, 2} },
50 { {-58, 3}, {-42, 4}, {-46, 4}, { 37, 5}, {-36, 4},
51 { 29, 4}, {-29, 4}, { 25, 4}, {-23, 4}, { 20, 4},
52 {-17, 4}, { 16, 4}, {-12, 4}, { 12, 3}, {-10, 4},
53 { 7, 3}, { -4, 4}, { 3, 3}, { -1, 3}, { 1, 3} },
54 { {-59, 3}, {-45, 5}, {-50, 4}, { 38, 4}, {-39, 4},
55 { 32, 4}, {-30, 4}, { 25, 3}, {-23, 3}, { 20, 3},
56 {-20, 3}, { 16, 3}, {-13, 3}, { 10, 3}, { -7, 3},
57 { 3, 3}, { 0, 3}, { -1, 3}, { 2, 3}, { -1, 2} }
61 /** Scaled PARCOR values used for the first two PARCOR coefficients.
62 * To be indexed by the Rice coded indices.
63 * Generated by: parcor_scaled_values[i] = 32 + ((i * (i+1)) << 7) - (1 << 20)
64 * Actual values are divided by 32 in order to be stored in 16 bits.
66 static const int16_t parcor_scaled_values[] = {
67 -1048544 / 32, -1048288 / 32, -1047776 / 32, -1047008 / 32,
68 -1045984 / 32, -1044704 / 32, -1043168 / 32, -1041376 / 32,
69 -1039328 / 32, -1037024 / 32, -1034464 / 32, -1031648 / 32,
70 -1028576 / 32, -1025248 / 32, -1021664 / 32, -1017824 / 32,
71 -1013728 / 32, -1009376 / 32, -1004768 / 32, -999904 / 32,
72 -994784 / 32, -989408 / 32, -983776 / 32, -977888 / 32,
73 -971744 / 32, -965344 / 32, -958688 / 32, -951776 / 32,
74 -944608 / 32, -937184 / 32, -929504 / 32, -921568 / 32,
75 -913376 / 32, -904928 / 32, -896224 / 32, -887264 / 32,
76 -878048 / 32, -868576 / 32, -858848 / 32, -848864 / 32,
77 -838624 / 32, -828128 / 32, -817376 / 32, -806368 / 32,
78 -795104 / 32, -783584 / 32, -771808 / 32, -759776 / 32,
79 -747488 / 32, -734944 / 32, -722144 / 32, -709088 / 32,
80 -695776 / 32, -682208 / 32, -668384 / 32, -654304 / 32,
81 -639968 / 32, -625376 / 32, -610528 / 32, -595424 / 32,
82 -580064 / 32, -564448 / 32, -548576 / 32, -532448 / 32,
83 -516064 / 32, -499424 / 32, -482528 / 32, -465376 / 32,
84 -447968 / 32, -430304 / 32, -412384 / 32, -394208 / 32,
85 -375776 / 32, -357088 / 32, -338144 / 32, -318944 / 32,
86 -299488 / 32, -279776 / 32, -259808 / 32, -239584 / 32,
87 -219104 / 32, -198368 / 32, -177376 / 32, -156128 / 32,
88 -134624 / 32, -112864 / 32, -90848 / 32, -68576 / 32,
89 -46048 / 32, -23264 / 32, -224 / 32, 23072 / 32,
90 46624 / 32, 70432 / 32, 94496 / 32, 118816 / 32,
91 143392 / 32, 168224 / 32, 193312 / 32, 218656 / 32,
92 244256 / 32, 270112 / 32, 296224 / 32, 322592 / 32,
93 349216 / 32, 376096 / 32, 403232 / 32, 430624 / 32,
94 458272 / 32, 486176 / 32, 514336 / 32, 542752 / 32,
95 571424 / 32, 600352 / 32, 629536 / 32, 658976 / 32,
96 688672 / 32, 718624 / 32, 748832 / 32, 779296 / 32,
97 810016 / 32, 840992 / 32, 872224 / 32, 903712 / 32,
98 935456 / 32, 967456 / 32, 999712 / 32, 1032224 / 32
102 /** Gain values of p(0) for long-term prediction.
103 * To be indexed by the Rice coded indices.
105 static const uint8_t ltp_gain_values [4][4] = {
113 /** Inter-channel weighting factors for multi-channel correlation.
114 * To be indexed by the Rice coded indices.
116 static const int16_t mcc_weightings[] = {
117 204, 192, 179, 166, 153, 140, 128, 115,
118 102, 89, 76, 64, 51, 38, 25, 12,
119 0, -12, -25, -38, -51, -64, -76, -89,
120 -102, -115, -128, -140, -153, -166, -179, -192
124 /** Tail codes used in arithmetic coding using block Gilbert-Moore codes.
126 static const uint8_t tail_code[16][6] = {
127 { 74, 44, 25, 13, 7, 3},
128 { 68, 42, 24, 13, 7, 3},
129 { 58, 39, 23, 13, 7, 3},
130 {126, 70, 37, 19, 10, 5},
131 {132, 70, 37, 20, 10, 5},
132 {124, 70, 38, 20, 10, 5},
133 {120, 69, 37, 20, 11, 5},
134 {116, 67, 37, 20, 11, 5},
135 {108, 66, 36, 20, 10, 5},
136 {102, 62, 36, 20, 10, 5},
137 { 88, 58, 34, 19, 10, 5},
138 {162, 89, 49, 25, 13, 7},
139 {156, 87, 49, 26, 14, 7},
140 {150, 86, 47, 26, 14, 7},
141 {142, 84, 47, 26, 14, 7},
142 {131, 79, 46, 26, 14, 7}
154 uint32_t samples; ///< number of samples, 0xFFFFFFFF if unknown
155 int resolution; ///< 000 = 8-bit; 001 = 16-bit; 010 = 24-bit; 011 = 32-bit
156 int floating; ///< 1 = IEEE 32-bit floating-point, 0 = integer
157 int frame_length; ///< frame length for each frame (last frame may differ)
158 int ra_distance; ///< distance between RA frames (in frames, 0...255)
159 enum RA_Flag ra_flag; ///< indicates where the size of ra units is stored
160 int adapt_order; ///< adaptive order: 1 = on, 0 = off
161 int coef_table; ///< table index of Rice code parameters
162 int long_term_prediction; ///< long term prediction (LTP): 1 = on, 0 = off
163 int max_order; ///< maximum prediction order (0..1023)
164 int block_switching; ///< number of block switching levels
165 int bgmc; ///< "Block Gilbert-Moore Code": 1 = on, 0 = off (Rice coding only)
166 int sb_part; ///< sub-block partition
167 int joint_stereo; ///< joint stereo: 1 = on, 0 = off
168 int mc_coding; ///< extended inter-channel coding (multi channel coding): 1 = on, 0 = off
169 int chan_config; ///< indicates that a chan_config_info field is present
170 int chan_sort; ///< channel rearrangement: 1 = on, 0 = off
171 int rlslms; ///< use "Recursive Least Square-Least Mean Square" predictor: 1 = on, 0 = off
172 int chan_config_info; ///< mapping of channels to loudspeaker locations. Unused until setting channel configuration is implemented.
173 int *chan_pos; ///< original channel positions
188 AVCodecContext *avctx;
189 ALSSpecificConfig sconf;
191 unsigned int cur_frame_length; ///< length of the current frame to decode
192 unsigned int frame_id; ///< the frame ID / number of the current frame
193 unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
194 unsigned int num_blocks; ///< number of blocks used in the current frame
195 uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
196 unsigned int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
197 int ltp_lag_length; ///< number of bits used for ltp lag value
198 int *use_ltp; ///< contains use_ltp flags for all channels
199 int *ltp_lag; ///< contains ltp lag values for all channels
200 int **ltp_gain; ///< gain values for ltp 5-tap filter for a channel
201 int *ltp_gain_buffer; ///< contains all gain values for ltp 5-tap filter
202 int32_t **quant_cof; ///< quantized parcor coefficients for a channel
203 int32_t *quant_cof_buffer; ///< contains all quantized parcor coefficients
204 int32_t **lpc_cof; ///< coefficients of the direct form prediction filter for a channel
205 int32_t *lpc_cof_buffer; ///< contains all coefficients of the direct form prediction filter
206 int32_t *lpc_cof_reversed_buffer; ///< temporary buffer to set up a reversed versio of lpc_cof_buffer
207 ALSChannelData **chan_data; ///< channel data for multi-channel correlation
208 ALSChannelData *chan_data_buffer; ///< contains channel data for all channels
209 int *reverted_channels; ///< stores a flag for each reverted channel
210 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
211 int32_t **raw_samples; ///< decoded raw samples for each channel
212 int32_t *raw_buffer; ///< contains all decoded raw samples including carryover samples
217 unsigned int block_length; ///< number of samples within the block
218 unsigned int ra_block; ///< if true, this is a random access block
219 int const_block; ///< if true, this is a constant value block
220 int32_t const_val; ///< the sample value of a constant block
221 int js_blocks; ///< true if this block contains a difference signal
222 unsigned int shift_lsbs; ///< shift of values for this block
223 unsigned int opt_order; ///< prediction order of this block
224 int store_prev_samples;///< if true, carryover samples have to be stored
225 int *use_ltp; ///< if true, long-term prediction is used
226 int *ltp_lag; ///< lag value for long-term prediction
227 int *ltp_gain; ///< gain values for ltp 5-tap filter
228 int32_t *quant_cof; ///< quantized parcor coefficients
229 int32_t *lpc_cof; ///< coefficients of the direct form prediction
230 int32_t *raw_samples; ///< decoded raw samples / residuals for this block
231 int32_t *prev_raw_samples; ///< contains unshifted raw samples from the previous block
232 int32_t *raw_other; ///< decoded raw samples of the other channel of a channel pair
236 static av_cold void dprint_specific_config(ALSDecContext *ctx)
239 AVCodecContext *avctx = ctx->avctx;
240 ALSSpecificConfig *sconf = &ctx->sconf;
242 dprintf(avctx, "resolution = %i\n", sconf->resolution);
243 dprintf(avctx, "floating = %i\n", sconf->floating);
244 dprintf(avctx, "frame_length = %i\n", sconf->frame_length);
245 dprintf(avctx, "ra_distance = %i\n", sconf->ra_distance);
246 dprintf(avctx, "ra_flag = %i\n", sconf->ra_flag);
247 dprintf(avctx, "adapt_order = %i\n", sconf->adapt_order);
248 dprintf(avctx, "coef_table = %i\n", sconf->coef_table);
249 dprintf(avctx, "long_term_prediction = %i\n", sconf->long_term_prediction);
250 dprintf(avctx, "max_order = %i\n", sconf->max_order);
251 dprintf(avctx, "block_switching = %i\n", sconf->block_switching);
252 dprintf(avctx, "bgmc = %i\n", sconf->bgmc);
253 dprintf(avctx, "sb_part = %i\n", sconf->sb_part);
254 dprintf(avctx, "joint_stereo = %i\n", sconf->joint_stereo);
255 dprintf(avctx, "mc_coding = %i\n", sconf->mc_coding);
256 dprintf(avctx, "chan_config = %i\n", sconf->chan_config);
257 dprintf(avctx, "chan_sort = %i\n", sconf->chan_sort);
258 dprintf(avctx, "RLSLMS = %i\n", sconf->rlslms);
259 dprintf(avctx, "chan_config_info = %i\n", sconf->chan_config_info);
264 /** Reads an ALSSpecificConfig from a buffer into the output struct.
266 static av_cold int read_specific_config(ALSDecContext *ctx)
270 int i, config_offset, crc_enabled;
271 MPEG4AudioConfig m4ac;
272 ALSSpecificConfig *sconf = &ctx->sconf;
273 AVCodecContext *avctx = ctx->avctx;
274 uint32_t als_id, header_size, trailer_size;
276 init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);
278 config_offset = ff_mpeg4audio_get_config(&m4ac, avctx->extradata,
279 avctx->extradata_size);
281 if (config_offset < 0)
284 skip_bits_long(&gb, config_offset);
286 if (get_bits_left(&gb) < (30 << 3))
289 // read the fixed items
290 als_id = get_bits_long(&gb, 32);
291 avctx->sample_rate = m4ac.sample_rate;
292 skip_bits_long(&gb, 32); // sample rate already known
293 sconf->samples = get_bits_long(&gb, 32);
294 avctx->channels = m4ac.channels;
295 skip_bits(&gb, 16); // number of channels already knwon
296 skip_bits(&gb, 3); // skip file_type
297 sconf->resolution = get_bits(&gb, 3);
298 sconf->floating = get_bits1(&gb);
299 skip_bits1(&gb); // skip msb_first
300 sconf->frame_length = get_bits(&gb, 16) + 1;
301 sconf->ra_distance = get_bits(&gb, 8);
302 sconf->ra_flag = get_bits(&gb, 2);
303 sconf->adapt_order = get_bits1(&gb);
304 sconf->coef_table = get_bits(&gb, 2);
305 sconf->long_term_prediction = get_bits1(&gb);
306 sconf->max_order = get_bits(&gb, 10);
307 sconf->block_switching = get_bits(&gb, 2);
308 sconf->bgmc = get_bits1(&gb);
309 sconf->sb_part = get_bits1(&gb);
310 sconf->joint_stereo = get_bits1(&gb);
311 sconf->mc_coding = get_bits1(&gb);
312 sconf->chan_config = get_bits1(&gb);
313 sconf->chan_sort = get_bits1(&gb);
314 crc_enabled = get_bits1(&gb);
315 sconf->rlslms = get_bits1(&gb);
316 skip_bits(&gb, 5); // skip 5 reserved bits
317 skip_bits1(&gb); // skip aux_data_enabled
320 // check for ALSSpecificConfig struct
321 if (als_id != MKBETAG('A','L','S','\0'))
324 ctx->cur_frame_length = sconf->frame_length;
326 // read channel config
327 if (sconf->chan_config)
328 sconf->chan_config_info = get_bits(&gb, 16);
329 // TODO: use this to set avctx->channel_layout
332 // read channel sorting
333 if (sconf->chan_sort && avctx->channels > 1) {
334 int chan_pos_bits = av_ceil_log2(avctx->channels);
335 int bits_needed = avctx->channels * chan_pos_bits + 7;
336 if (get_bits_left(&gb) < bits_needed)
339 if (!(sconf->chan_pos = av_malloc(avctx->channels * sizeof(*sconf->chan_pos))))
340 return AVERROR(ENOMEM);
342 for (i = 0; i < avctx->channels; i++)
343 sconf->chan_pos[i] = get_bits(&gb, chan_pos_bits);
346 // TODO: use this to actually do channel sorting
348 sconf->chan_sort = 0;
352 // read fixed header and trailer sizes,
353 // if size = 0xFFFFFFFF then there is no data field!
354 if (get_bits_left(&gb) < 64)
357 header_size = get_bits_long(&gb, 32);
358 trailer_size = get_bits_long(&gb, 32);
359 if (header_size == 0xFFFFFFFF)
361 if (trailer_size == 0xFFFFFFFF)
364 ht_size = ((int64_t)(header_size) + (int64_t)(trailer_size)) << 3;
367 // skip the header and trailer data
368 if (get_bits_left(&gb) < ht_size)
371 if (ht_size > INT32_MAX)
374 skip_bits_long(&gb, ht_size);
379 if (get_bits_left(&gb) < 32)
382 skip_bits_long(&gb, 32);
386 // no need to read the rest of ALSSpecificConfig (ra_unit_size & aux data)
388 dprint_specific_config(ctx);
394 /** Checks the ALSSpecificConfig for unsupported features.
396 static int check_specific_config(ALSDecContext *ctx)
398 ALSSpecificConfig *sconf = &ctx->sconf;
401 // report unsupported feature and set error value
402 #define MISSING_ERR(cond, str, errval) \
405 av_log_missing_feature(ctx->avctx, str, 0); \
410 MISSING_ERR(sconf->floating, "Floating point decoding", -1);
411 MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", -1);
412 MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
418 /** Parses the bs_info field to extract the block partitioning used in
419 * block switching mode, refer to ISO/IEC 14496-3, section 11.6.2.
421 static void parse_bs_info(const uint32_t bs_info, unsigned int n,
422 unsigned int div, unsigned int **div_blocks,
423 unsigned int *num_blocks)
425 if (n < 31 && ((bs_info << n) & 0x40000000)) {
426 // if the level is valid and the investigated bit n is set
427 // then recursively check both children at bits (2n+1) and (2n+2)
430 parse_bs_info(bs_info, n + 1, div, div_blocks, num_blocks);
431 parse_bs_info(bs_info, n + 2, div, div_blocks, num_blocks);
433 // else the bit is not set or the last level has been reached
434 // (bit implicitly not set)
442 /** Reads and decodes a Rice codeword.
444 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
446 int max = get_bits_left(gb) - k;
447 int q = get_unary(gb, 0, max);
448 int r = k ? get_bits1(gb) : !(q & 1);
452 q += get_bits_long(gb, k - 1);
460 /** Converts PARCOR coefficient k to direct filter coefficient.
462 static void parcor_to_lpc(unsigned int k, const int32_t *par, int32_t *cof)
466 for (i = 0, j = k - 1; i < j; i++, j--) {
467 int tmp1 = ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
468 cof[j] += ((MUL64(par[k], cof[i]) + (1 << 19)) >> 20);
472 cof[i] += ((MUL64(par[k], cof[j]) + (1 << 19)) >> 20);
478 /** Reads block switching field if necessary and sets actual block sizes.
479 * Also assures that the block sizes of the last frame correspond to the
480 * actual number of samples.
482 static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
485 ALSSpecificConfig *sconf = &ctx->sconf;
486 GetBitContext *gb = &ctx->gb;
487 unsigned int *ptr_div_blocks = div_blocks;
490 if (sconf->block_switching) {
491 unsigned int bs_info_len = 1 << (sconf->block_switching + 2);
492 *bs_info = get_bits_long(gb, bs_info_len);
493 *bs_info <<= (32 - bs_info_len);
497 parse_bs_info(*bs_info, 0, 0, &ptr_div_blocks, &ctx->num_blocks);
499 // The last frame may have an overdetermined block structure given in
500 // the bitstream. In that case the defined block structure would need
501 // more samples than available to be consistent.
502 // The block structure is actually used but the block sizes are adapted
503 // to fit the actual number of available samples.
504 // Example: 5 samples, 2nd level block sizes: 2 2 2 2.
505 // This results in the actual block sizes: 2 2 1 0.
506 // This is not specified in 14496-3 but actually done by the reference
507 // codec RM22 revision 2.
508 // This appears to happen in case of an odd number of samples in the last
509 // frame which is actually not allowed by the block length switching part
511 // The ALS conformance files feature an odd number of samples in the last
514 for (b = 0; b < ctx->num_blocks; b++)
515 div_blocks[b] = ctx->sconf.frame_length >> div_blocks[b];
517 if (ctx->cur_frame_length != ctx->sconf.frame_length) {
518 unsigned int remaining = ctx->cur_frame_length;
520 for (b = 0; b < ctx->num_blocks; b++) {
521 if (remaining < div_blocks[b]) {
522 div_blocks[b] = remaining;
523 ctx->num_blocks = b + 1;
527 remaining -= div_blocks[b];
533 /** Reads the block data for a constant block
535 static void read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
537 ALSSpecificConfig *sconf = &ctx->sconf;
538 AVCodecContext *avctx = ctx->avctx;
539 GetBitContext *gb = &ctx->gb;
542 bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
543 bd->js_blocks = get_bits1(gb);
545 // skip 5 reserved bits
548 if (bd->const_block) {
549 unsigned int const_val_bits = sconf->floating ? 24 : avctx->bits_per_raw_sample;
550 bd->const_val = get_sbits_long(gb, const_val_bits);
553 // ensure constant block decoding by reusing this field
558 /** Decodes the block data for a constant block
560 static void decode_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
562 int smp = bd->block_length;
563 int32_t val = bd->const_val;
564 int32_t *dst = bd->raw_samples;
566 // write raw samples into buffer
572 /** Reads the block data for a non-constant block
574 static int read_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
576 ALSSpecificConfig *sconf = &ctx->sconf;
577 AVCodecContext *avctx = ctx->avctx;
578 GetBitContext *gb = &ctx->gb;
582 unsigned int sub_blocks, log2_sub_blocks, sb_length;
583 unsigned int start = 0;
584 unsigned int opt_order;
586 int32_t *quant_cof = bd->quant_cof;
587 int32_t *current_res;
590 // ensure variable block decoding by reusing this field
594 bd->js_blocks = get_bits1(gb);
596 opt_order = bd->opt_order;
598 // determine the number of subblocks for entropy decoding
599 if (!sconf->bgmc && !sconf->sb_part) {
602 if (sconf->bgmc && sconf->sb_part)
603 log2_sub_blocks = get_bits(gb, 2);
605 log2_sub_blocks = 2 * get_bits1(gb);
608 sub_blocks = 1 << log2_sub_blocks;
610 // do not continue in case of a damaged stream since
611 // block_length must be evenly divisible by sub_blocks
612 if (bd->block_length & (sub_blocks - 1)) {
613 av_log(avctx, AV_LOG_WARNING,
614 "Block length is not evenly divisible by the number of subblocks.\n");
618 sb_length = bd->block_length >> log2_sub_blocks;
621 s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
622 for (k = 1; k < sub_blocks; k++)
623 s[k] = s[k - 1] + decode_rice(gb, 2);
625 for (k = 0; k < sub_blocks; k++) {
630 s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
631 for (k = 1; k < sub_blocks; k++)
632 s[k] = s[k - 1] + decode_rice(gb, 0);
636 bd->shift_lsbs = get_bits(gb, 4) + 1;
638 bd->store_prev_samples = (bd->js_blocks && bd->raw_other) || bd->shift_lsbs;
641 if (!sconf->rlslms) {
642 if (sconf->adapt_order) {
643 int opt_order_length = av_ceil_log2(av_clip((bd->block_length >> 3) - 1,
644 2, sconf->max_order + 1));
645 bd->opt_order = get_bits(gb, opt_order_length);
647 bd->opt_order = sconf->max_order;
650 opt_order = bd->opt_order;
655 if (sconf->coef_table == 3) {
658 // read coefficient 0
659 quant_cof[0] = 32 * parcor_scaled_values[get_bits(gb, 7)];
661 // read coefficient 1
663 quant_cof[1] = -32 * parcor_scaled_values[get_bits(gb, 7)];
665 // read coefficients 2 to opt_order
666 for (k = 2; k < opt_order; k++)
667 quant_cof[k] = get_bits(gb, 7);
672 // read coefficient 0 to 19
673 k_max = FFMIN(opt_order, 20);
674 for (k = 0; k < k_max; k++) {
675 int rice_param = parcor_rice_table[sconf->coef_table][k][1];
676 int offset = parcor_rice_table[sconf->coef_table][k][0];
677 quant_cof[k] = decode_rice(gb, rice_param) + offset;
680 // read coefficients 20 to 126
681 k_max = FFMIN(opt_order, 127);
682 for (; k < k_max; k++)
683 quant_cof[k] = decode_rice(gb, 2) + (k & 1);
685 // read coefficients 127 to opt_order
686 for (; k < opt_order; k++)
687 quant_cof[k] = decode_rice(gb, 1);
689 quant_cof[0] = 32 * parcor_scaled_values[quant_cof[0] + 64];
692 quant_cof[1] = -32 * parcor_scaled_values[quant_cof[1] + 64];
695 for (k = 2; k < opt_order; k++)
696 quant_cof[k] = (quant_cof[k] << 14) + (add_base << 13);
700 // read LTP gain and lag values
701 if (sconf->long_term_prediction) {
702 *bd->use_ltp = get_bits1(gb);
705 bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
706 bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
708 bd->ltp_gain[2] = ltp_gain_values[get_unary(gb, 0, 4)][get_bits(gb, 2)];
710 bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
711 bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
713 *bd->ltp_lag = get_bits(gb, ctx->ltp_lag_length);
714 *bd->ltp_lag += FFMAX(4, opt_order + 1);
718 // read first value and residuals in case of a random access block
721 bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
723 bd->raw_samples[1] = decode_rice(gb, s[0] + 3);
725 bd->raw_samples[2] = decode_rice(gb, s[0] + 1);
727 start = FFMIN(opt_order, 3);
730 // read all residuals
732 unsigned int delta[sub_blocks];
733 unsigned int k [sub_blocks];
734 unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
735 unsigned int i = start;
737 // read most significant bits
742 ff_bgmc_decode_init(gb, &high, &low, &value);
744 current_res = bd->raw_samples + start;
746 for (sb = 0; sb < sub_blocks; sb++, i = 0) {
747 k [sb] = s[sb] > b ? s[sb] - b : 0;
748 delta[sb] = 5 - s[sb] + k[sb];
750 ff_bgmc_decode(gb, sb_length, current_res,
751 delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
753 current_res += sb_length;
756 ff_bgmc_decode_end(gb);
759 // read least significant bits and tails
761 current_res = bd->raw_samples + start;
763 for (sb = 0; sb < sub_blocks; sb++, i = 0) {
764 unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
765 unsigned int cur_k = k[sb];
766 unsigned int cur_s = s[sb];
768 for (; i < sb_length; i++) {
769 int32_t res = *current_res;
771 if (res == cur_tail_code) {
772 unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
775 res = decode_rice(gb, cur_s);
778 res += (max_msb ) << cur_k;
780 res -= (max_msb - 1) << cur_k;
783 if (res > cur_tail_code)
793 res |= get_bits_long(gb, cur_k);
797 *current_res++ = res;
801 current_res = bd->raw_samples + start;
803 for (sb = 0; sb < sub_blocks; sb++, start = 0)
804 for (; start < sb_length; start++)
805 *current_res++ = decode_rice(gb, s[sb]);
808 if (!sconf->mc_coding || ctx->js_switch)
815 /** Decodes the block data for a non-constant block
817 static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
819 ALSSpecificConfig *sconf = &ctx->sconf;
820 unsigned int block_length = bd->block_length;
821 unsigned int smp = 0;
823 int opt_order = bd->opt_order;
826 int32_t *quant_cof = bd->quant_cof;
827 int32_t *lpc_cof = bd->lpc_cof;
828 int32_t *raw_samples = bd->raw_samples;
829 int32_t *raw_samples_end = bd->raw_samples + bd->block_length;
830 int32_t *lpc_cof_reversed = ctx->lpc_cof_reversed_buffer;
832 // reverse long-term prediction
836 for (ltp_smp = FFMAX(*bd->ltp_lag - 2, 0); ltp_smp < block_length; ltp_smp++) {
837 int center = ltp_smp - *bd->ltp_lag;
838 int begin = FFMAX(0, center - 2);
839 int end = center + 3;
840 int tab = 5 - (end - begin);
845 for (base = begin; base < end; base++, tab++)
846 y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
848 raw_samples[ltp_smp] += y >> 7;
852 // reconstruct all samples from residuals
854 for (smp = 0; smp < opt_order; smp++) {
857 for (sb = 0; sb < smp; sb++)
858 y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
860 *raw_samples++ -= y >> 20;
861 parcor_to_lpc(smp, quant_cof, lpc_cof);
864 for (k = 0; k < opt_order; k++)
865 parcor_to_lpc(k, quant_cof, lpc_cof);
867 // store previous samples in case that they have to be altered
868 if (bd->store_prev_samples)
869 memcpy(bd->prev_raw_samples, raw_samples - sconf->max_order,
870 sizeof(*bd->prev_raw_samples) * sconf->max_order);
872 // reconstruct difference signal for prediction (joint-stereo)
873 if (bd->js_blocks && bd->raw_other) {
874 int32_t *left, *right;
876 if (bd->raw_other > raw_samples) { // D = R - L
878 right = bd->raw_other;
879 } else { // D = R - L
880 left = bd->raw_other;
884 for (sb = -1; sb >= -sconf->max_order; sb--)
885 raw_samples[sb] = right[sb] - left[sb];
888 // reconstruct shifted signal
890 for (sb = -1; sb >= -sconf->max_order; sb--)
891 raw_samples[sb] >>= bd->shift_lsbs;
894 // reverse linear prediction coefficients for efficiency
895 lpc_cof = lpc_cof + opt_order;
897 for (sb = 0; sb < opt_order; sb++)
898 lpc_cof_reversed[sb] = lpc_cof[-(sb + 1)];
900 // reconstruct raw samples
901 raw_samples = bd->raw_samples + smp;
902 lpc_cof = lpc_cof_reversed + opt_order;
904 for (; raw_samples < raw_samples_end; raw_samples++) {
907 for (sb = -opt_order; sb < 0; sb++)
908 y += MUL64(lpc_cof[sb], raw_samples[sb]);
910 *raw_samples -= y >> 20;
913 raw_samples = bd->raw_samples;
915 // restore previous samples in case that they have been altered
916 if (bd->store_prev_samples)
917 memcpy(raw_samples - sconf->max_order, bd->prev_raw_samples,
918 sizeof(*raw_samples) * sconf->max_order);
924 /** Reads the block data.
926 static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
928 GetBitContext *gb = &ctx->gb;
930 // read block type flag and read the samples accordingly
932 if (read_var_block_data(ctx, bd))
935 read_const_block_data(ctx, bd);
942 /** Decodes the block data.
944 static int decode_block(ALSDecContext *ctx, ALSBlockData *bd)
948 // read block type flag and read the samples accordingly
950 decode_const_block_data(ctx, bd);
951 else if (decode_var_block_data(ctx, bd))
954 // TODO: read RLSLMS extension data
957 for (smp = 0; smp < bd->block_length; smp++)
958 bd->raw_samples[smp] <<= bd->shift_lsbs;
964 /** Reads and decodes block data successively.
966 static int read_decode_block(ALSDecContext *ctx, ALSBlockData *bd)
970 ret = read_block(ctx, bd);
975 ret = decode_block(ctx, bd);
981 /** Computes the number of samples left to decode for the current frame and
982 * sets these samples to zero.
984 static void zero_remaining(unsigned int b, unsigned int b_max,
985 const unsigned int *div_blocks, int32_t *buf)
987 unsigned int count = 0;
990 count += div_blocks[b];
993 memset(buf, 0, sizeof(*buf) * count);
997 /** Decodes blocks independently.
999 static int decode_blocks_ind(ALSDecContext *ctx, unsigned int ra_frame,
1000 unsigned int c, const unsigned int *div_blocks,
1001 unsigned int *js_blocks)
1006 memset(&bd, 0, sizeof(ALSBlockData));
1008 bd.ra_block = ra_frame;
1009 bd.use_ltp = ctx->use_ltp;
1010 bd.ltp_lag = ctx->ltp_lag;
1011 bd.ltp_gain = ctx->ltp_gain[0];
1012 bd.quant_cof = ctx->quant_cof[0];
1013 bd.lpc_cof = ctx->lpc_cof[0];
1014 bd.prev_raw_samples = ctx->prev_raw_samples;
1015 bd.raw_samples = ctx->raw_samples[c];
1018 for (b = 0; b < ctx->num_blocks; b++) {
1020 bd.block_length = div_blocks[b];
1022 if (read_decode_block(ctx, &bd)) {
1023 // damaged block, write zero for the rest of the frame
1024 zero_remaining(b, ctx->num_blocks, div_blocks, bd.raw_samples);
1027 bd.raw_samples += div_blocks[b];
1035 /** Decodes blocks dependently.
1037 static int decode_blocks(ALSDecContext *ctx, unsigned int ra_frame,
1038 unsigned int c, const unsigned int *div_blocks,
1039 unsigned int *js_blocks)
1041 ALSSpecificConfig *sconf = &ctx->sconf;
1042 unsigned int offset = 0;
1046 memset(bd, 0, 2 * sizeof(ALSBlockData));
1048 bd[0].ra_block = ra_frame;
1049 bd[0].use_ltp = ctx->use_ltp;
1050 bd[0].ltp_lag = ctx->ltp_lag;
1051 bd[0].ltp_gain = ctx->ltp_gain[0];
1052 bd[0].quant_cof = ctx->quant_cof[0];
1053 bd[0].lpc_cof = ctx->lpc_cof[0];
1054 bd[0].prev_raw_samples = ctx->prev_raw_samples;
1055 bd[0].js_blocks = *js_blocks;
1057 bd[1].ra_block = ra_frame;
1058 bd[1].use_ltp = ctx->use_ltp;
1059 bd[1].ltp_lag = ctx->ltp_lag;
1060 bd[1].ltp_gain = ctx->ltp_gain[0];
1061 bd[1].quant_cof = ctx->quant_cof[0];
1062 bd[1].lpc_cof = ctx->lpc_cof[0];
1063 bd[1].prev_raw_samples = ctx->prev_raw_samples;
1064 bd[1].js_blocks = *(js_blocks + 1);
1066 // decode all blocks
1067 for (b = 0; b < ctx->num_blocks; b++) {
1070 bd[0].shift_lsbs = 0;
1071 bd[1].shift_lsbs = 0;
1073 bd[0].block_length = div_blocks[b];
1074 bd[1].block_length = div_blocks[b];
1076 bd[0].raw_samples = ctx->raw_samples[c ] + offset;
1077 bd[1].raw_samples = ctx->raw_samples[c + 1] + offset;
1079 bd[0].raw_other = bd[1].raw_samples;
1080 bd[1].raw_other = bd[0].raw_samples;
1082 if(read_decode_block(ctx, &bd[0]) || read_decode_block(ctx, &bd[1])) {
1083 // damaged block, write zero for the rest of the frame
1084 zero_remaining(b, ctx->num_blocks, div_blocks, bd[0].raw_samples);
1085 zero_remaining(b, ctx->num_blocks, div_blocks, bd[1].raw_samples);
1089 // reconstruct joint-stereo blocks
1090 if (bd[0].js_blocks) {
1091 if (bd[1].js_blocks)
1092 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel pair!\n");
1094 for (s = 0; s < div_blocks[b]; s++)
1095 bd[0].raw_samples[s] = bd[1].raw_samples[s] - bd[0].raw_samples[s];
1096 } else if (bd[1].js_blocks) {
1097 for (s = 0; s < div_blocks[b]; s++)
1098 bd[1].raw_samples[s] = bd[1].raw_samples[s] + bd[0].raw_samples[s];
1101 offset += div_blocks[b];
1106 // store carryover raw samples,
1107 // the others channel raw samples are stored by the calling function.
1108 memmove(ctx->raw_samples[c] - sconf->max_order,
1109 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1110 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1116 /** Reads the channel data.
1118 static int read_channel_data(ALSDecContext *ctx, ALSChannelData *cd, int c)
1120 GetBitContext *gb = &ctx->gb;
1121 ALSChannelData *current = cd;
1122 unsigned int channels = ctx->avctx->channels;
1125 while (entries < channels && !(current->stop_flag = get_bits1(gb))) {
1126 current->master_channel = get_bits_long(gb, av_ceil_log2(channels));
1128 if (current->master_channel >= channels) {
1129 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid master channel!\n");
1133 if (current->master_channel != c) {
1134 current->time_diff_flag = get_bits1(gb);
1135 current->weighting[0] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1136 current->weighting[1] = mcc_weightings[av_clip(decode_rice(gb, 2) + 14, 0, 32)];
1137 current->weighting[2] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1139 if (current->time_diff_flag) {
1140 current->weighting[3] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1141 current->weighting[4] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1142 current->weighting[5] = mcc_weightings[av_clip(decode_rice(gb, 1) + 16, 0, 32)];
1144 current->time_diff_sign = get_bits1(gb);
1145 current->time_diff_index = get_bits(gb, ctx->ltp_lag_length - 3) + 3;
1153 if (entries == channels) {
1154 av_log(ctx->avctx, AV_LOG_ERROR, "Damaged channel data!\n");
1163 /** Recursively reverts the inter-channel correlation for a block.
1165 static int revert_channel_correlation(ALSDecContext *ctx, ALSBlockData *bd,
1166 ALSChannelData **cd, int *reverted,
1167 unsigned int offset, int c)
1169 ALSChannelData *ch = cd[c];
1170 unsigned int dep = 0;
1171 unsigned int channels = ctx->avctx->channels;
1178 while (dep < channels && !ch[dep].stop_flag) {
1179 revert_channel_correlation(ctx, bd, cd, reverted, offset,
1180 ch[dep].master_channel);
1185 if (dep == channels) {
1186 av_log(ctx->avctx, AV_LOG_WARNING, "Invalid channel correlation!\n");
1190 bd->use_ltp = ctx->use_ltp + c;
1191 bd->ltp_lag = ctx->ltp_lag + c;
1192 bd->ltp_gain = ctx->ltp_gain[c];
1193 bd->lpc_cof = ctx->lpc_cof[c];
1194 bd->quant_cof = ctx->quant_cof[c];
1195 bd->raw_samples = ctx->raw_samples[c] + offset;
1198 while (!ch[dep].stop_flag) {
1200 unsigned int begin = 1;
1201 unsigned int end = bd->block_length - 1;
1203 int32_t *master = ctx->raw_samples[ch[dep].master_channel] + offset;
1205 if (ch[dep].time_diff_flag) {
1206 int t = ch[dep].time_diff_index;
1208 if (ch[dep].time_diff_sign) {
1215 for (smp = begin; smp < end; smp++) {
1217 MUL64(ch[dep].weighting[0], master[smp - 1 ]) +
1218 MUL64(ch[dep].weighting[1], master[smp ]) +
1219 MUL64(ch[dep].weighting[2], master[smp + 1 ]) +
1220 MUL64(ch[dep].weighting[3], master[smp - 1 + t]) +
1221 MUL64(ch[dep].weighting[4], master[smp + t]) +
1222 MUL64(ch[dep].weighting[5], master[smp + 1 + t]);
1224 bd->raw_samples[smp] += y >> 7;
1227 for (smp = begin; smp < end; smp++) {
1229 MUL64(ch[dep].weighting[0], master[smp - 1]) +
1230 MUL64(ch[dep].weighting[1], master[smp ]) +
1231 MUL64(ch[dep].weighting[2], master[smp + 1]);
1233 bd->raw_samples[smp] += y >> 7;
1244 /** Reads the frame data.
1246 static int read_frame_data(ALSDecContext *ctx, unsigned int ra_frame)
1248 ALSSpecificConfig *sconf = &ctx->sconf;
1249 AVCodecContext *avctx = ctx->avctx;
1250 GetBitContext *gb = &ctx->gb;
1251 unsigned int div_blocks[32]; ///< block sizes.
1253 unsigned int js_blocks[2];
1255 uint32_t bs_info = 0;
1257 // skip the size of the ra unit if present in the frame
1258 if (sconf->ra_flag == RA_FLAG_FRAMES && ra_frame)
1259 skip_bits_long(gb, 32);
1261 if (sconf->mc_coding && sconf->joint_stereo) {
1262 ctx->js_switch = get_bits1(gb);
1266 if (!sconf->mc_coding || ctx->js_switch) {
1267 int independent_bs = !sconf->joint_stereo;
1269 for (c = 0; c < avctx->channels; c++) {
1273 get_block_sizes(ctx, div_blocks, &bs_info);
1275 // if joint_stereo and block_switching is set, independent decoding
1276 // is signaled via the first bit of bs_info
1277 if (sconf->joint_stereo && sconf->block_switching)
1281 // if this is the last channel, it has to be decoded independently
1282 if (c == avctx->channels - 1)
1285 if (independent_bs) {
1286 if (decode_blocks_ind(ctx, ra_frame, c, div_blocks, js_blocks))
1291 if (decode_blocks(ctx, ra_frame, c, div_blocks, js_blocks))
1297 // store carryover raw samples
1298 memmove(ctx->raw_samples[c] - sconf->max_order,
1299 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1300 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1302 } else { // multi-channel coding
1305 int *reverted_channels = ctx->reverted_channels;
1306 unsigned int offset = 0;
1308 for (c = 0; c < avctx->channels; c++)
1309 if (ctx->chan_data[c] < ctx->chan_data_buffer) {
1310 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid channel data!\n");
1314 memset(&bd, 0, sizeof(ALSBlockData));
1315 memset(reverted_channels, 0, sizeof(*reverted_channels) * avctx->channels);
1317 bd.ra_block = ra_frame;
1318 bd.prev_raw_samples = ctx->prev_raw_samples;
1320 get_block_sizes(ctx, div_blocks, &bs_info);
1322 for (b = 0; b < ctx->num_blocks; b++) {
1324 bd.block_length = div_blocks[b];
1326 for (c = 0; c < avctx->channels; c++) {
1327 bd.use_ltp = ctx->use_ltp + c;
1328 bd.ltp_lag = ctx->ltp_lag + c;
1329 bd.ltp_gain = ctx->ltp_gain[c];
1330 bd.lpc_cof = ctx->lpc_cof[c];
1331 bd.quant_cof = ctx->quant_cof[c];
1332 bd.raw_samples = ctx->raw_samples[c] + offset;
1333 bd.raw_other = NULL;
1335 read_block(ctx, &bd);
1336 if (read_channel_data(ctx, ctx->chan_data[c], c))
1340 for (c = 0; c < avctx->channels; c++)
1341 if (revert_channel_correlation(ctx, &bd, ctx->chan_data,
1342 reverted_channels, offset, c))
1345 for (c = 0; c < avctx->channels; c++) {
1346 bd.use_ltp = ctx->use_ltp + c;
1347 bd.ltp_lag = ctx->ltp_lag + c;
1348 bd.ltp_gain = ctx->ltp_gain[c];
1349 bd.lpc_cof = ctx->lpc_cof[c];
1350 bd.quant_cof = ctx->quant_cof[c];
1351 bd.raw_samples = ctx->raw_samples[c] + offset;
1352 decode_block(ctx, &bd);
1355 memset(reverted_channels, 0, avctx->channels * sizeof(*reverted_channels));
1356 offset += div_blocks[b];
1360 // store carryover raw samples
1361 for (c = 0; c < avctx->channels; c++)
1362 memmove(ctx->raw_samples[c] - sconf->max_order,
1363 ctx->raw_samples[c] - sconf->max_order + sconf->frame_length,
1364 sizeof(*ctx->raw_samples[c]) * sconf->max_order);
1367 // TODO: read_diff_float_data
1373 /** Decodes an ALS frame.
1375 static int decode_frame(AVCodecContext *avctx,
1376 void *data, int *data_size,
1379 ALSDecContext *ctx = avctx->priv_data;
1380 ALSSpecificConfig *sconf = &ctx->sconf;
1381 const uint8_t *buffer = avpkt->data;
1382 int buffer_size = avpkt->size;
1383 int invalid_frame, size;
1384 unsigned int c, sample, ra_frame, bytes_read, shift;
1386 init_get_bits(&ctx->gb, buffer, buffer_size * 8);
1388 // In the case that the distance between random access frames is set to zero
1389 // (sconf->ra_distance == 0) no frame is treated as a random access frame.
1390 // For the first frame, if prediction is used, all samples used from the
1391 // previous frame are assumed to be zero.
1392 ra_frame = sconf->ra_distance && !(ctx->frame_id % sconf->ra_distance);
1394 // the last frame to decode might have a different length
1395 if (sconf->samples != 0xFFFFFFFF)
1396 ctx->cur_frame_length = FFMIN(sconf->samples - ctx->frame_id * (uint64_t) sconf->frame_length,
1397 sconf->frame_length);
1399 ctx->cur_frame_length = sconf->frame_length;
1401 // decode the frame data
1402 if ((invalid_frame = read_frame_data(ctx, ra_frame) < 0))
1403 av_log(ctx->avctx, AV_LOG_WARNING,
1404 "Reading frame data failed. Skipping RA unit.\n");
1408 // check for size of decoded data
1409 size = ctx->cur_frame_length * avctx->channels *
1410 (av_get_bits_per_sample_format(avctx->sample_fmt) >> 3);
1412 if (size > *data_size) {
1413 av_log(avctx, AV_LOG_ERROR, "Decoded data exceeds buffer size.\n");
1419 // transform decoded frame into output format
1420 #define INTERLEAVE_OUTPUT(bps) \
1422 int##bps##_t *dest = (int##bps##_t*) data; \
1423 shift = bps - ctx->avctx->bits_per_raw_sample; \
1424 for (sample = 0; sample < ctx->cur_frame_length; sample++) \
1425 for (c = 0; c < avctx->channels; c++) \
1426 *dest++ = ctx->raw_samples[c][sample] << shift; \
1429 if (ctx->avctx->bits_per_raw_sample <= 16) {
1430 INTERLEAVE_OUTPUT(16)
1432 INTERLEAVE_OUTPUT(32)
1435 bytes_read = invalid_frame ? buffer_size :
1436 (get_bits_count(&ctx->gb) + 7) >> 3;
1442 /** Uninitializes the ALS decoder.
1444 static av_cold int decode_end(AVCodecContext *avctx)
1446 ALSDecContext *ctx = avctx->priv_data;
1448 av_freep(&ctx->sconf.chan_pos);
1450 ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
1452 av_freep(&ctx->use_ltp);
1453 av_freep(&ctx->ltp_lag);
1454 av_freep(&ctx->ltp_gain);
1455 av_freep(&ctx->ltp_gain_buffer);
1456 av_freep(&ctx->quant_cof);
1457 av_freep(&ctx->lpc_cof);
1458 av_freep(&ctx->quant_cof_buffer);
1459 av_freep(&ctx->lpc_cof_buffer);
1460 av_freep(&ctx->lpc_cof_reversed_buffer);
1461 av_freep(&ctx->prev_raw_samples);
1462 av_freep(&ctx->raw_samples);
1463 av_freep(&ctx->raw_buffer);
1464 av_freep(&ctx->chan_data);
1465 av_freep(&ctx->chan_data_buffer);
1466 av_freep(&ctx->reverted_channels);
1472 /** Initializes the ALS decoder.
1474 static av_cold int decode_init(AVCodecContext *avctx)
1477 unsigned int channel_size;
1479 ALSDecContext *ctx = avctx->priv_data;
1480 ALSSpecificConfig *sconf = &ctx->sconf;
1483 if (!avctx->extradata) {
1484 av_log(avctx, AV_LOG_ERROR, "Missing required ALS extradata.\n");
1488 if (read_specific_config(ctx)) {
1489 av_log(avctx, AV_LOG_ERROR, "Reading ALSSpecificConfig failed.\n");
1494 if (check_specific_config(ctx)) {
1500 ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
1502 if (sconf->floating) {
1503 avctx->sample_fmt = SAMPLE_FMT_FLT;
1504 avctx->bits_per_raw_sample = 32;
1506 avctx->sample_fmt = sconf->resolution > 1
1507 ? SAMPLE_FMT_S32 : SAMPLE_FMT_S16;
1508 avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
1511 // set lag value for long-term prediction
1512 ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
1513 (avctx->sample_rate >= 192000);
1515 // allocate quantized parcor coefficient buffer
1516 num_buffers = sconf->mc_coding ? avctx->channels : 1;
1518 ctx->quant_cof = av_malloc(sizeof(*ctx->quant_cof) * num_buffers);
1519 ctx->lpc_cof = av_malloc(sizeof(*ctx->lpc_cof) * num_buffers);
1520 ctx->quant_cof_buffer = av_malloc(sizeof(*ctx->quant_cof_buffer) *
1521 num_buffers * sconf->max_order);
1522 ctx->lpc_cof_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1523 num_buffers * sconf->max_order);
1524 ctx->lpc_cof_reversed_buffer = av_malloc(sizeof(*ctx->lpc_cof_buffer) *
1527 if (!ctx->quant_cof || !ctx->lpc_cof ||
1528 !ctx->quant_cof_buffer || !ctx->lpc_cof_buffer ||
1529 !ctx->lpc_cof_reversed_buffer) {
1530 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1531 return AVERROR(ENOMEM);
1534 // assign quantized parcor coefficient buffers
1535 for (c = 0; c < num_buffers; c++) {
1536 ctx->quant_cof[c] = ctx->quant_cof_buffer + c * sconf->max_order;
1537 ctx->lpc_cof[c] = ctx->lpc_cof_buffer + c * sconf->max_order;
1540 // allocate and assign lag and gain data buffer for ltp mode
1541 ctx->use_ltp = av_mallocz(sizeof(*ctx->use_ltp) * num_buffers);
1542 ctx->ltp_lag = av_malloc (sizeof(*ctx->ltp_lag) * num_buffers);
1543 ctx->ltp_gain = av_malloc (sizeof(*ctx->ltp_gain) * num_buffers);
1544 ctx->ltp_gain_buffer = av_malloc (sizeof(*ctx->ltp_gain_buffer) *
1547 if (!ctx->use_ltp || !ctx->ltp_lag ||
1548 !ctx->ltp_gain || !ctx->ltp_gain_buffer) {
1549 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1551 return AVERROR(ENOMEM);
1554 for (c = 0; c < num_buffers; c++)
1555 ctx->ltp_gain[c] = ctx->ltp_gain_buffer + c * 5;
1557 // allocate and assign channel data buffer for mcc mode
1558 if (sconf->mc_coding) {
1559 ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
1561 ctx->chan_data = av_malloc(sizeof(ALSChannelData) *
1563 ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
1566 if (!ctx->chan_data_buffer || !ctx->chan_data || !ctx->reverted_channels) {
1567 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1569 return AVERROR(ENOMEM);
1572 for (c = 0; c < num_buffers; c++)
1573 ctx->chan_data[c] = ctx->chan_data_buffer + c;
1575 ctx->chan_data = NULL;
1576 ctx->chan_data_buffer = NULL;
1577 ctx->reverted_channels = NULL;
1580 avctx->frame_size = sconf->frame_length;
1581 channel_size = sconf->frame_length + sconf->max_order;
1583 ctx->prev_raw_samples = av_malloc (sizeof(*ctx->prev_raw_samples) * sconf->max_order);
1584 ctx->raw_buffer = av_mallocz(sizeof(*ctx-> raw_buffer) * avctx->channels * channel_size);
1585 ctx->raw_samples = av_malloc (sizeof(*ctx-> raw_samples) * avctx->channels);
1587 // allocate previous raw sample buffer
1588 if (!ctx->prev_raw_samples || !ctx->raw_buffer|| !ctx->raw_samples) {
1589 av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
1591 return AVERROR(ENOMEM);
1594 // assign raw samples buffers
1595 ctx->raw_samples[0] = ctx->raw_buffer + sconf->max_order;
1596 for (c = 1; c < avctx->channels; c++)
1597 ctx->raw_samples[c] = ctx->raw_samples[c - 1] + channel_size;
1603 /** Flushes (resets) the frame ID after seeking.
1605 static av_cold void flush(AVCodecContext *avctx)
1607 ALSDecContext *ctx = avctx->priv_data;
1613 AVCodec als_decoder = {
1617 sizeof(ALSDecContext),
1623 .capabilities = CODEC_CAP_SUBFRAMES,
1624 .long_name = NULL_IF_CONFIG_SMALL("MPEG-4 Audio Lossless Coding (ALS)"),